4 speed bellhousing

There are basically two passenger car (OEM) choices. One for the 130-tooth flywheel (10.5" clutch or 10.95" scalloped clutch) and for the 143-tooth flywheel (true 11" clutch). These came in different configurations and front bearing retainer sizes, but those are the flywheel/clutch sizes. Some of the choice is determined by what trans you have.