Preparing the old Dou for re-skinning

[MMXIX]

Some of the suggestions from this thread about removing fujaku residue might apply:

Fujaku Glue Removal

Hey all. I’ve got a second hand shamisen that recently arrived, and it’s beautiful - but there’s residue from a fujaku that’s really harshing my enjoyment. Anyone have ideas for removing the residue without stripping off the finish? I haven’t tried anything yet. It just arrived.