If you were installing a V8, you could buy a new cross member.
I have a 1962 235 engine and a 1967 sm420. The bellhousing is the original 1954 one that came with the truck. Originally the truck was 6 volts, so the flywheel, starter and clutch are 1954. I'm not sure that a newer flywheel and clutch would fit my bellhousing. My point is that it all has to work together so choose carefully.
What happened to the original 1951 bellhousing? Your engine and transmission should work with it.
