My first car was a '60 chevy, and I had at least a dozen different tranny's in that car over the years. How do you have the back of the engine supported now? If you're hanging from the motor mounts and exhaust you've likely torn your motor mounts apart and will be replacing them - ask me how I know.... Like Pat says, a bottle jack or floor jack and a piece of 2x4 under the oil pan will work fine. There should be plenty of room for the bare tranny (no shift linkage) to slip into place, but like Pat says you can break the exhaust pipe supports and drop the back of the engine a few inches if you really need clearance. Again like Pat says, watch your distributor to firewall clearance. If you get the throwout bearing on the tranny shaft with the fork in place you're fine to stab it, and it is not a "gentle" process to get the tranny shaft into the pilot bearing and pushed up tight, even if you've used a pilot shaft to align the clutch disc. I don't think I ever had a throwout bearing come out of the fork - the fork is hooked at the fulcrum point and clutch rod, and once the tranny shaft is pushed through it cannot go anywhere, right?