This implementation allows the RH6 to be attainable without mods but rare to find
The car will spawn in the furthermost right corner of the underground parking garage in Algonquin (pictured)

Using openIV
IV: place the wpl in GTAIV/pc/data/maps/manhat/manhat08.img
TBOGT: place the wpl in GTAIV/TBoGT/pc/data/maps/manhat/manhat08.img