For the current custom I'm working on I plan on dyeing Fireflight (the upper arms, upper legs, waist, and any pontential rub points that are brown) and Skydive (everthing that's in that garish lavender). The problem is that I think Fireflight's limbs (circled in red) are made of unpaintable plastic and I don't know how well that kind of plastic accepts dye. Also is it possible to only just dye only a bit of a part, like dyeing the ball sockets(circled in green) using a rack or stand of some sort? Also how likely is it for dye to seep through after the dyed part is painted and discolor the new paint? Edit: I forgot to mention that I plan on using black dye.