I once had a Model A body that had all square recess head screws. They weren't very common back then, but I did some research and found that Robertson (square recess) screws were a Canadian invention and that's where that particular body had been assembled. Henry Ford started using them on the Model T, at their Windsor, Ontario plant. The patent for Robertson screws expired in 1975, and they became more common.
I also found this bit about clutch drive screws (patented by a guy named Joseph F. Fieg (so it might have been called the Fieg screw.):
Because of the very positive engagement between driver and screw, it was well suited to mass production and was adopted by Chevrolet for their cars, trucks and buses from the 1940's through the 1950's. As a result, it was sometimes referred to as a "Chevrolet screw." It could also be found on older tractors, where it was used to secure sheet metal parts.
(In contrast, General Motors adopted the Phillips screw, patented in 1936, first on the 1936 Cadillac and later for their trucks.)
On this
blog site.. I added the emphasis in bold.
