[Kennuck]

I worked in the plastic industry a few years back and we would "flame treat" stressed plastic to get rid of the white stress marks. This works for faded plastic as well. You pass the flame over the plastic quickly and the fade disappears. It works by melting a very thin top layer of plastic and restores the color. Don't let the flame stop on the surface or it will melt the part. Get an old piece of faded plastic and practice on it first. You will be amazed. You can also use a heat gun.