1. Open your shopping.dat with notepad (it's in data folder, you can copy it to a folder inside modloader, make sure to have only 1 shopping.dat inside modloader).

2. Find the CarMods section (usually it's the first one). It looks like this:

	section CarMods
		#name,			nametag,	stats to change,		price   
		<lots of tuning parts data here>
	end						

3. Add these lines in the section (anywhere between "section CarMods" and the first "end" after it):

		#comet3
		exh_comet3_a		COM3EXA		respect 0 	sexy 0		500
		fbmp_comet3_a		COM3FBA		respect 0 	sexy 0		1250
		fbmp_comet3_b		COM3FBB		respect 0 	sexy 0		1650
		misc_a_comet3		COM3MAA		respect 0 	sexy 0		1000
		misc_b_comet3		COM3MBA		respect 0 	sexy 0		750
		misc_c_comet3		COM3MCA		respect 0 	sexy 0		250
		fbb_comet3_a		COM3FAR		respect 0 	sexy 0		100
		rbmp_comet3_a		COM3RBA		respect 0 	sexy 0		1050
		bbb_comet3_a		COM3RAR		respect 0 	sexy 0		100
		spl_comet3_a		COM3SPA		respect 0 	sexy 0		500
		spl_comet3_b		COM3SPB		respect 0 	sexy 0		750
		spl_comet3_c		COM3SPC		respect 0 	sexy 0		950
		
4. Find the carmod1 section (it's TransFender section). Usually it looks like this:

section carmod1 # Normal Cars
	type CarMods
		<lots of tuning items data here>
	end
	
5. Add these lines in the section (anywhere between "type CarMods" and the first "end" after it):

		#Comet3
		item exh_comet3_a
		item fbmp_comet3_a
		item fbmp_comet3_b	
		item misc_a_comet3
		item misc_b_comet3
		item misc_c_comet3
		item fbb_comet3_a
		item rbmp_comet3_a
		item bbb_comet3_a
		item spl_comet3_a
		item spl_comet3_b
		item spl_comet3_c
		
6. Save the changes and close the file.