Chris/Dave,
Thanks for your comments. The only reference that I have been able to locate is green over cobalt blue for the unit colours. Of course there a multitude of varieties of both colours.
Early in my search I was told how widely the troops applied their markings to their vehicles. The pictures that I have found seem to prove that point. I've attached a picture of my formation sign for the Ist Canadian Infantry Division, and one from the RCDs on a Humber (??) for the correct period. Fortunately it's only paint and can be redone, if need be.
Peter
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