GM 8.5 10 bolt swap

A friend of mine, long ago, who later sold me his V code 440-6 RR, in winter of 68 he and I were attending Navy electronics schools on Treasure Island. He had a 65, Chevelle, had bought a totaled 67-68 'maro and swapped the engine/ trans and wheels into the Chevelle. During the year or so I was there, he broke TWO 10 bolts and snapped the input shaft off a Muncie which I "got" to help fix.