I was wondering about the '91 donor too, maybe he meant an '81?
If I owned that thing I'd be installing a 5-speed tranny in it (I have access to one in a 260E) OTOH, registration in this state might be a bit complicated. If you didn't do it properly you would be receiving notices to have it smogged! Wouldn't that be fun? take it to a smog station and see if they noticed anything odd about the emissions levels. Ha!