I’ve just purchased a 3 speed gearbox that was removed from a 1949 3100 Chevy truck. Its condition was reported to be operational when it was removed months ago. In the process of basic external degreasing and cleaning I removed the three plugs for servicing it. The shape of the rear housing plug used for replenishment of oil looked different than the servicing plug on our 1948 tranny, see attached photo. Can anyone one tell me if this the correct form shape of the plug?
