are you trying to remove part of the paint job and wants an even surface back again?
if so.. wet sand smooth the whole area with find grit sand paper eg.. 1500 and up. Once the whole headstock is smooth, clear coat it for about 4-5 layers at least. Sand it flat down and do your polishing again. The idea is to coat a layer of clear and flatten that clear instead of flattening what your guitar is left with.