Personally, I have painted a few and I have painted my R/C truck bodies. I DO NOT recommend scuffing up the inside at all. Make sure the plastic is washed with hot soap and water nothing else is needed and dry it with your air compressor or a can of compressed air or a hairdryer. This is not the bumper of your car, it;s Poly Carb. make sure your body shop guys knows this. Your local hobby shop has all the right paints for this and they will NEVER peal off. They are even gas/nitro proof. Go to the hobby shop and pick the color you want and give that spray can or differnt color cans to your body shop guy. That paint is made just for this type of plastic. If you scuff the inside it will have a flat or dull look to it when your done. The hobby shop has candy chromes and every color you can think of. Doug