Hmm, nope we can't tell colour from those numbers. The good news is that the numbers match with when the cars were built, but there's no way to tell colour from them. I thought they were still stamping the colours on the plates in '72? 1981 is a bit beyond my experience, but I think you need to find the foil sticker. They often get painted over, so look for a rectangular sticker on the radiator shroud.
Also do you have any photos of the colours? We can probably give you some idea.
Tim