>Maybe the folks in St. Louis can scratch through what little paint is left on the PPKX 5568
Been there. Done that.
Only thing for sure I could confirm from my hour with that car is that the underframe and trucks were once painted black with a white / light lettering, and the interior was once white with a dark gray / black lettering. The car sides have a light powdery “chalky" residue. But I was unable to locate any "chips" of paint on the ends or sides. Perhaps they have already collected such in the years since they got her in 1986, or can find such by removal of parts.