My friends wife gave me her Grand Fathers Lionel 342e Set for some maintenance.
Basic simple stuff replacing wires that had become brittle for the light pickups in the cars etc, and some simple lube maintenance on the 318 Engine.
My problem is the cars have some Black Smudges (look sort of like finger prints) that appears to be dried up Tree Sap from fingers that had been mixed up in Real Christmas Trees at some time in their life. They haven't been under a tree in 20 years or more so they would have spent many holiday seasons under REAL Trees and I am having issues cleaning these smudges off the paint. I don't want to use anything that will remove of destroy the finish as they are in really good condition for 90+ years old trains.
I have tried Dawn Dish soap, it doesn't seem to cut through the stuff.
I also tried WD-40 on a small patch but it seems to have dulled the finish.
I'm guessing I could bring that back with some Car polish but figured I post here and see what other ideas you guys might come back with before going further?