Passenger cars from the floor shift days until 1954 used the same bolt pattern. I'm not sure just how the vacuum shift worked, but 60 years ago everyone that had it got rid of it and I'm sure it hasn't gotten any better. In fact a lot of kits were offered to remove the vacuum shift from 1939 through 1948. NOS vacuum shift units appear on eBay quite regularly and right now I see one of the vacuum shift delete kits on eBay. The problem is in the linkage, not the transmission itself.