Peds

To add variations to a ped model:

1. Open "ModelVariations_Peds.ini"
2. In the end of the file enter the id (or the model name) of the model you want to add variations inside [] brackets (e.g if you want to add variations to a LS cop [280] or [lapd1])
3. In a new line, enter the city you want then enter a '=' and then the id or model name of the variation you want to the city you want (e.g Global=155).
4. You can use a comma to add multiple variations (e.g Global=155,167).

Example:

[7]
Global=heck1,155
LosSantos=249

Outside Los Santos heck1 and 155 will be used. Inside Los Santos all 3 will be used.

To add more models go to the end of the file and repeat the above steps.

[7]
Global=heck1,155
LosSantos=249
[army]
Global=army,wmypizz,wmybell

This example changes the pizza guy (id 155) to a cop while you are in LS and a valet in LV:

[155]
LosSantos=280
LasVenturas=189

The parent model (the model inside the brackets) should be used only once (1 set of brackets). Each set of brackets must have one model inside.

Available cities and areas to use (Global is for every city):
Global
LosSantos
SanFierro
LasVenturas
Countryside
Desert
TierraRobada
BoneCounty
RedCounty
Blueberry
Montgomery
Dillimore
PalominoCreek
FlintCounty
Whetstone
AngelPine

You can also specify any zone in the game you want. All zones can be found in data\info.zon.
Example line from info.zon:

SFDWT1, 0, -1982.32, 744.17, -6.10352e-005, -1871.72, 1274.26, 200.0, 1, SFDWT

Add the zone name (first name on the line, all characters must be UPPERCASE) to the ini:

[155]
AngelPine=
SFDWT1=

You can also have variations for specific interiors. Just use the interior's name.
This example replaces security in the Four Dragons casino with Triads:

[164]
TRICAS=117,118
[163]
TRICAS=117,118

You can find all the interior names here:
https://gtamods.com/wiki/Interior

You can use a "Wanted" filter on each ped to set which wanted level their variations appear in (Wanted1 to Wanted6). You must first add the variation to a city:

[280]
Global=155,167
Wanted1=155
Wanted2=167

On wanted level 1 (and when not the player is wanted) the LS cops will spawn as pizza guys.
On wanted level 2 the LS cops will spawn as Cluckin Bell guys.
On wanted level 3 and above they will spawn using both variations (no filter).
Each id in the filters must exist once.

The variations you add REPLACE the original. If you want the original to appear you must add it.
The variations will only appear in the city you added it in if the original spawns in that city by default.
You can add a variation many times (to the same line) to give it a higher priority (e.g Global=155,155,167).
If you add a variation to, for example, Red County and one to Montgomery they both will spawn in Montgomery because Montgomery is inside Red County (this does not apply to zones from info.zon).
You can set 'DontInheritBehaviour=1' to stop variations from inheriting stats (fear/respect etc). Example:

[280]
LosSantos=wmypizz,wmybell
DontInheritBehaviour=1

Now the fast food guys that replace the cops will run away when hit.

You can set the variations on a city or zone to 0 to stop that ped from spawning there. For example, to stop MALE01 from spawning at Los Santos:

[7]
LosSantos=0

Variations set in zones will override variations set in cities unless you set MergeZonesWithCities to 1. Example:

[280]
LosSantos=18,20
GAN1=16,17
MergeZonesWithCities=1

The ini for the ped variations also contains the following options:

'EnableCloneRemover' does not work for scripted peds.
You can use ";" (at the line start) to comment out a line.
Variations of CJ's Girlfriends are not supported.

Ped Weapons

To add weapon variations to a model (ModelVariations_PedWeapons.ini):

You can add variations to a specific weapon id (so the weapon variations will appear only if the ped has that weapon) or you can add a weapon to a specific slot (the weapon variations will replace any weapon in that slot).

The ped must already have that weapon (if the variations are for a specific weapon id) or any weapon in that slot (if the variations are for a slot).

You can use the ped model instead of its id. (e.g [lapd1] instead of [280]). For the weapons you have to use the weapon id.

To add weapon id variations you add WEAPON plus the weapon id (these override the SLOT variations). Example:

[280]
WEAPON22=23,24

This replaces the LS cops' Pistol with either a Silenced Pistol or a Desert Eagle.

To add a slot variation you add SLOT plus the weapon id. Example:

[280]
SLOT2=23,24

You can also add weapon id and slot variations for specific zones.
To do so you add the zone name plus _WEAPON or _SLOT and then the weapon id. Example:

[280]
GAN1_SLOT2=24
GAN2_SLOT2=24

Zone variations replace global variations (e.g GAN1_SLOT2 replaces SLOT2) unless you set 'MergeZonesWithGlobal=1':

[280]
SLOT2=23
GAN1_SLOT2=24
GAN2_SLOT2=24
MergeZonesWithGlobal=1

You can use WEAPONFORCE to force a ped to spawn with specific weapons even if he doesn't have any weapons in that slot:

[280]
WEAPONFORCE=10,14
GAN1_WEAPONFORCE=18
GAN2_WEAPONFORCE=18
MergeZonesWithGlobal=1

Weapon slots:
0 - Brass Knuckles and fist
1 - Melee weapons
2 - Pistols
3 - Shotguns
4 - Submachine guns
5 - Assault rifles
6 - Sniper and country rifles
7 - Heavy weapons
8 - Thrown
9 - Equipment (camera etc)
10 - Gifts (flowers etc)
11 - Goggles and parachute
12 - Satchel detonator

Weapon IDs: http://hotmist.ddo.jp/id/weapon.html

Vehicles

To add vehicle variations:

1. Open "ModelVariations_Vehicles.ini"
2. In the end of the file enter the id (or the model name) of the model you want to add variations inside [] brackets (e.g if you want to add variations to the car "Alpha" [602] or [alpha])
3. In a new line, enter the city you want (you can find them in the peds example) then enter a '=' and then the id or model name of the variation you want to the city you want (e.g Global=602).
4. You can use a comma to add multiple variations (e.g Global=421,405).
5. (Optional) If you want you can add specific variations to appear during specific wanted levels.

You can specify any zone in the game you want. (See Ped Variations above).

For example this replaces the LS cop car with a Merit at wanted level 1, a Sunrise at level 2 and both (since the entries are empty) at higher levels:

[596]
LosSantos=551,550
Wanted1=551
Wanted2=550

If you add a variation to 2 or more models you must use “ParentModel” and set 1 model as the parent model (even if you set it to a different city/zone).

[596]
LosSantos=550
[598]
LosSantos=550
[550]
ParentModel=596

The variations must always be of the same type as the original model and with at least the same number of doors (e.g you cannot assign a bike as a variation to a car).
The "Wanted" options act as filters. You must first add the variation to a city. Each id and group in the filters must exist once.
The variations you add REPLACE the original. If you want the original to appear you must add it.
The variations will only appear in the city you added it in if the original spawns in that city by default.
You can add a variation many times (to the same line) to give it a higher priority.
You can set "ChangeOnlyParked=1" to a model to only change cars of that model that spawn parked, not cars in traffic.
You can set the variations on a city or zone to 0 to stop that vehicle from spawning there. For example, to stop Bobcat from spawning at Los Santos:

[422]
LosSantos=0

Variations set in zones will override variations set in cities unless you set MergeZonesWithCities to 1. Example:

[596]
Global=596,421,507,405
DriverGroup1=249
PassengerGroup1=243,244,245
DriverGroup2=232
PassengerGroup2=236,234,235
GAN1=Group1,421
LosSantos=Group2
MergeZonesWithCities=1

You can set an emergency car's variation light positions by setting "LightX" "LightY" "LightZ" and "LightWidth". These are float values (with a dot e.g 0.5).
You can also set the color by setting "LightR", "LightG", "LightB" and "LightA". It uses values from 0 to 255.
If the model has changing colors (like the cop cars) you can also use "LightR2", "LightG2", "LightB2" and "LightA2" the change the second color.
They must be set on the variation not on the original model.
Example:

[407]
Global=421
[421]
LightWidth=0.6
LightZ=-0.5
LightY=-3
LightR=6
LightG=244
LightB=33
LightA=255
LightR2=255
LightG2=100
LightB2=99
LightA2=255

Vehicle occupants (driver and passengers):
You can specify the driver and passengers of the vehicle by using "Drivers=" and "Passengers=". Just add the models you want to appear as drivers or as passengers.
The options "ReplaceDriver" and "ReplacePassengers" allow you to choose whether you allow the original driver or passengers to spawn.
If you want the original driver or passengers to never spawn (only your added models will appear) set them to 1.
"ReplaceDriver" and "ReplacePassengers" affect the variations too (this does not apply to groups). So if you have added a variation then it will also spawn with these drivers and passengers.
You can make specific groups of vehicle occupants by adding ped models to "DriverGroupX" and "PassengerGroupX" (Replace the X with a number from 1 to 9). Both must be set.
You can set vehicles to appear only with the groups you added by setting "UseOnlyGroups" to 1 on the model you want. Otherwise half the time they will appear with other peds.
You can set "Passengers" to 0 to force vehicles to spawn without passengers.

You can specify wanted level filters, zones and cities for vehicle occupant groups. Example:

[596]
Global=596,421,507,405
DriverGroup1=249
PassengerGroup1=243,244,245
DriverGroup2=232
PassengerGroup2=236,234,235
DriverGroup3=29
PassengerGroup3=28,27
Wanted2=596,421,Group1
Wanted3=596,507,Group2
GAN1=Group1,Group3
LosSantos=Group2
UseOnlyGroups=1

What should happen in the above example:

The LS Police car will some times spawn as a Washington, an Elegant or a Sentinel.
In Los Santos it will always spawn with Group2 occupants only when it spawns as a Police Car.
In GAN1 (which is the northern part of Ganton) it will spawn with Group1 or Group3 when it spawns as a Police Car.
During wanted level 2 it will only spawn as a Police Car or a Washington and with Group2 at LosSantos (invalid filter, no Group1 in Los Santos) and Group1 in GAN1 if it spawns as a Police Car.
During wanted level 3 it will only spawn as a Police Car or an Elegant and with Group2 at LosSantos and Group1 or Group3 in GAN1 (invalid filter, no Group2 in GAN1) if it spawns as a Police Car.

Wanted levels that don't have anything assigned spawn with all variations and occupants.
Occupant groups do not work for ambulances and firetrucks.

You can set car tuning parts for car models that spawn in traffic. Example:

[jester]
Global=exh_a_j,exh_c_j,fbmp_a_j,fbmp_c_j,nto_b_l,nto_b_s,nto_b_tw,rbmp_a_j,rbmp_c_j,spl_a_j_b,spl_c_j_b,rf_a_j,rf_c_j,wg_l_a_j,wg_l_c_j,nto_b_s
TuningFullBodykit=1

You just add them like you add variations (make sure there are no spaces). Each part spawns randomly.
'TuningFullBodykit' forces the front bumper, rear bumper and side skirts to spawn together.
Check carmods.dat for what tuning parts each car supports. Unsupported parts will cause a crash.
To add hydraulics to a car use 'hydralics'. To add bass boost use 'stereo'.
You can also use 'TuningRarity' on a model to set how often that car will appear with tuning parts.
'TuningRarity' on 0 means it will never appear with tuning parts. 1 means always. 2 means 50% of the time. 3 means 33% of the time, 4 means 25% and so on.
If you don't set TuningRarity, the default value (3) will be used.

The ini for the vehicle variations also contains the following options:

'EnableSideMissionsForAllScripts' should be 0 if you don't use any mod that adds side missions.
'LoadAllVehicles' may need a memory increasing mod (like OpenLimitAdjuster) if you have replaced many cars with HD models.

Vehicle IDs: https://wiki.multitheftauto.com/wiki/Vehicle_IDs

Recommended to use with added peds/weapons/vehicles.
Tutorial: https://www.youtube.com/watch?v=IOsIuoON_2E

Some vehicle special features won't work unless you use a mod that enables them like ImVehFt or VehFuncs. Currently supported models:
Dumper
Firetruck
Mr. Whoopie
Rhino
Packer
Dozer
Cement Truck
Towtruck
Forklift
Tractor
Combine Harverster
Swat Tank
Cropduster
Stuntplane

Map with all zones
https://static.wikia.nocookie.net/gtawiki/images/4/40/TerritoriesNamesGTASA-map.png/revision/latest?cb=20160714130032

Recommended editor for ini files: Notepad++