This is the start of what will be several methods for removing paint, both factory and after market.
Removing non-factory paint using Mr. Clean Magic Eraser
My wife scored the best flea market find I've ever had, 30 figures for $12. Most of them just needed a new o-ring. As I was going through the pile of parts I came across a Stinger driver with an intact Cobra symbol. The problem was this figure must have had a horrible "death". He was covered in candle wax and red paint.
The wax came off with running hot water in the sink and some light scrubbing. The paint was an entirely different issue. It wasn't coming off. I was just about to drop him in some rubbing alcohol to eat away at the paint when I remembered the Mr. Clean Magic Eraser. The Magic Eraser is a cleaning sponge that when wet, can not only clean but easily removes skuff marks and even paint from floors and walls. We've used them around the house and they work really well, but this was the first time I was tempted to use it on a figure.
The idea here was to remove the paint without ruining the factory paint underneath. I started with the torso and then the arms, parts that were molded in grey. This way, if it was too abrassive on the plastic, then I could buff it out back to factory shine later. However, there was no need for that. Most of it came off within two-three passes. Next, I tried the back of the legs where the straps are. I wanted to see what would happen with the black factory paint. Would it come off? The red paint came off but the black paint looked pristine. So I tried scrubbing the front while still being very careful not to remove the black paint of the straps. Again, no problem. By the time I was going over the knife on his thigh, I wasn't even trying to be careful.
It took some elbow grease to get all the spots and I did end up using an X-acto knife where the paint got into the flashing of the mold lines. Overall it worked better than I expected. I wouldn't use it for removing paint from a fully painted figure, but maybe in a refining capacity after a soak in some paint remover. I do reccommend it for figure resoration purposes.