I bought rear Cobra brakes for my car and the calipers are powder coated red.  I bought them when I was planning on painting my car black.  Now that my car is not black, I think I want either black or silver calipers.  Is it possible to paint over powder coat and have a lasting durable finish or would I be better off selling the red calipers and picking up a new set of black or silver powder coated calipers?