A833 + clutch question : 68 318 engine

the bellhousing is another factor, some early 273 units only fit the small flywheel and 9.5" clutch-avoid it. some shops like to balance with the pressure plate-just in case she is out a little-but not necessary. the a833 takes a 30 spline/727 output yoke-and there are 2-small 7260 or large 7290 U joint. some a833 overdrive units have the smaller 904 spline yoke. there are 3 different rear hole sizes on bellhousings-4.3" , 4.8" , 5.1" and 3 corresponding transmission bolt on front bearing retainer outside diameter sizes.