I think the best thing would be to just add a new global variable. That was my plan. If the player got the paint job from T-Ray, the global would be set to one. Then, on the map scripts, at the create car procedure, if the global was triggered, then create the new car... if not, then the original car is created. Just copy everything there, pretty much, and replace the two pieces of new art you will need (for the car body and the trunk).