A friend of mine has a F@rd '88 E250 or 350 ambulance he still uses for training purposes. After 16 odd years, the diesel powerplant is getting clapped out. He called the dealer who said diesels can't be rebuilt and tried to sell him a new motor (w/install) for $4 grand.
Assuming the dealer was correct, can a 300 **** straight six swap in? Of course there are wiring and fuel system issues, I know. But an L6 gas motor could be rebuilt for half the dealer's qoute.