i think all of them were painted OD during that time. if it saw military service it should have property tags on it somewhere. not uncommon to see fifth disabled. but even though it may have never seen military service in my opinion OD would still be the color because of it's interesting time in history.
So that's truce it should have military tags on it but there isn't any to be found and on the engine block the lettering/stencil lettering in white is legible, did cat do this for the gov. or did the gov. do it after received?