Hi DC,
a few decades ago I bought a bargain Kawi 90cc 2-stroke for my boys after the PO had gotten it back from the kids that had stolen it.
Those kids had reckoned that fizzing their trophy flat black would disguise it.
I managed to wash off the black paint with rags soaked in acetone to show the bike's original Kawi green paint underneath.
You might be surprised to see your XS2's original paint still there if you try the acetone treatment.