When you intsall a car useing sprakiv it replaces the car it's "optimized for" for example if i install a police car and it's optimized for "police2" it will replace the police partrol car. What program do they use? if your talking about hte program that he uses to change the colour of the car it look to me he is useing the inGame Trainer http://www.gtaforums.com/index.php?showtopic=393676 I hope this helps Bazz