There are two different starter nose cones which space the starter drive pinion gear about 1/2" different side to side. If you get a starter for the big flywheel, it won't allow the drive teeth to engage the small one. One way to identify the different starters is to look at the position of the bolts that attach the starter to the block. On one of them, the bolts are directly across from each other, and on the other, the bolts are offset about 1 inch forward to back. I don't recall which one of the bolt arrangements is for the large-diameter flywheel/flex plate.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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