I have a beautiful Pink Bell 500 but the previous owner must have tried to bleach or chemically treat the body and ear piece and now its a much lighter pink than the inside, see pictures, and even has some whitish spots, circled. I usually treat my light color phones using the Dally 30 mix to removing browning but I would assume this phone is beyond that, anyone have any experience with this type of damage and have any tips for how to bring it back, is sanding my only option? Thanks...Tim