Hy fireguyfire, Happy New Year, your post confuses me, to clarify are you working on a Chevrolet or a GMC? The forties is not my area of expertise (if I have one) but I have never seen a Chevrolet or GMC engine painted silver from the factory, the two colours most often mentioned are gray and blue. Chevrolet and GMC inline sixes have never been flatheads that I'm aware of, the only silver flatheads that I have any experience with were manufactured by Chrysler corporation. Oldsmobile and Pontiac did make some flathead inline six cylinder engines that were installed in trucks up to 1936 I believe, so I'm not sure what you are working on.
