Removing paint from Lithography

[tinplatacis]

I recently bought several of Ives' 60 and 70 series passenger cars from the 1920's. There is a 62 chair car with a yellow stripe haphazardly sploshed across the side and a repainted roof, and a 73 observation with a painted end and roof. The original litho is intact, and from the looks of things so is the roof paint under the atrocious Tuscan someone brush painted, but I don't know how to remove the paint without possibly damaging the paint and printing underneath. Any help?

[sir james I]

Once painted, it's hard to save. A friend had some success with hobby shop paint remover but still lost some of the litho in heavly painted areas.

[LL675]

I work in a Litho plant, and the ink used is very thin. so any paint that is brushed or sprayed on will be a lot thicker. Good Luck El!