When the UTLX cars first painted on the C&TS, the cars were painted with a water based alkyd (sp?) enamel. I carefully sanded down the WP&Y paint to find the original UTLX #'s. There was discussion about sand blasting the cars to bare metal, but the NMSHPO office nixed that saying the underlying paint was part of the cars historic fabric and shouldn't be messed with. We went along with that, and being the old paint was in decent shape, we simply painted over it.
It seems that SHPO has had a change of heart as I think the cars are getting sandblasted down and repainted.