I would try some lacquer thinner. You may have to allow it to soften up the paint a little before rubbing it off with a cotton rag. Don't get any thinner on paint you don't want to remove.

Plan "b" would be to use paint stripper.


1941 Chevy 1 1/2-ton WW2 4x4 dump truck
In the Stovebolt Gallery
Lots more pictures