As far as the USMC is concerned, I would hypothesize that in WWII the marines got their tanks from the armor board and they likely were painted the same. They did have USA numbers and stars on many of them, others sometimes had a different font stencil with USMC on them.
IF they were repainted, it would have been 34052. That is what the USMC trucks were painted I believe.
I do know that by the 50s, and into Viet Nam, the Marines continued the 34052 fat dark green on the wheeled vehicles, and presumably on the armor as well. But I cannot confirm that with any direct knowledge.