@Twinkle-eye I have a magic eraser around here somewhere. I haven't tried it on a pony yet. Maybe I will give that a try on Confetti, as she has more of a spot problem, but her body is really all white besides those spots. I feel like Windy's more gray than pale purple, and needs more of an all-over solution. I'll try the acetone idea on her. You do just mean nail polish remover, right?
Also, when I try to look up that peroxide cream it just brings up a bunch of stuff for bleaching one's hair. Same stuff?! General question to anyone who uses a light box - what kind works for you?!