I have only torn down a '52 and a '53 truck engine and they both had fiber cam gears. I do not know the history of the engines, but the '52 had the original brass accordion style thermostat, all metal head gasket and original pistons. Indeed a small sample size, just thought I'd throw it out there.
Carl


1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission