Please pass along the things you do to get the crankcase to seal. I had the same problem with pulling vacuum in the crankcase...nobody makes the trick crankshaft seals to prevent leaks. What else do you have to do so a FE will pull vacuum?
66 Fairlane GT Silver Blue "BRUTE" Genesis 496/C4
66 Fairlane GT Nightmist Blue 428/TKO600
66 F250 Camper Special Rangoon Red 428/4-speed
2000 Lincoln LS Sport 5-speed