I'm not getting what you are asking.... I got the whole repainting part, but are you wanting to do it because of insurance?
Over on the Camaro message boards, there have been many discussions about a V6 to a V8 swap. Interestingly enough, some have said that if you go from a V6 to a V8 the car is still billed on the V6's rate for insurance. While this sounds nice, for emissions purposes the V8 is also tested and placed under V6 regulations in order to pass. Back to the point, since paint color is used to identify the car from a distance, it would probably need to be changed on the insurance card, but would fall under a custom paint category and wouldn't help the rates any. I could be wrong... I have yet to repaint any one of my cars a different color.
Insurance is done by VIN only. Any modifications done to the car don't matter to the insurance company. If you have a 2.5 T-Red SVT, expect to be billed for one through insurance till you get rid of it.