[storm9c1]

Yep, change the flexplate.

Depending on your state, he may not legally be allowed to tell you to exhange an engine unless it is a 100% stock replacement (ie: same motor). Some states are funny about engine swaps and emissions especially if it's a daily driver and not registered as an antique (or off-road use only). The easy test is to tell him it's an off-road 4-wheeler only. Then he may suddenly say "sure, that engine will work great!" Or he is just clueless and didn't want to deal with you.