The most common EMD color for the engineroom and locomotive interiror was a light grey. Some railroads specified a light tan and a few a light green. Everything inside the locomotive -- cab, engine room, engine, main generator, etc., got the same color. With the advent of safety cab locomotives some railroads began specifying a different color for the cab interior.
RWM
Bill
"Never try to teach a pig to sing. It wastes your time and annoys the pig"