Big block/3 on the tree?

My buddy Robert RIP... had a 68 or 69 D100 with a 3 on the tree. IDK which one. It was a 383 swapped to a 440. I asked why and he said why not. He wasn't much of a lead foot anyway. 1st gear is non synchronized on the A745 up to 68. The A230 69-71 "I think" didn't check the FSM. Craig