The only thing I know is that there were 2 different diameter input shafts used on the "1/4 ton" Jeeps. My OEM '72 box had the smaller (possibly 3/4" like the manual boxes) and a buds '73 had the larger (possibly 13/16"). My box went out in Tellico (MANUAL 'power steering" sucked bad!), but was able to borrow his for the weekend just swapping the belljoint.

I was given a "76" marked Sag box of unknown origin to replace mine that also needed the larger splined belljoint. Luckily, another bud had just completely replaced everything from the column down and gave me the larger belljoint from his late-'70s CJ.

You should be able to source a new yoke for the box end of your shaft if needed...