Flywheel, bellhousing questions 351C Manual
Darrell is right. As long as the balance is right, the flywheel can't tell the difference from a 302 to a 351C. Same bolt pattern, etc. You might run into one small problem that I found on my 157t, small bellhousing C4. Large starters won't fit: the starter body will hit the oil pan rail. So be prepared to use a late-model, PMGR starter, which is much smaller. Hopefully, what you have will fit.
\'65 Fairlane 351C/C4; \'31 Model A Coupe 460/C4 in progress, \'01 F150 4WD, 2003 Expedition (wife\'s)