swap
The guys here would rather get rid of a Powerstroke and swap in the IDI engine you already have!
That being said, yes its feasible. The best (easiest/cheapest) would probably be to find a wrecked donor vehicle with good engine. That way you'd have access to the whole wiring harness, all the electronics and the engine with all accessories and what not.
If you use the 7.3 Powerstroke your transmission should bolt up no problem. I'm not sure why the oil pan would have to be changed though. Seeing that in '94 you could get either the IDI, IDI turbo or Powerstroke straight from Ford I'd have to imagine that the engine would drop into place with minimal differences, possibly different motor mounts on the frame. But honesty I'm just guessing as far as that goes.
One thing that might be a hiccup, is getting stuff on your dash to interface well. If I read your post right, you have a 1990, which is the older dash with mechanical speedo. That shouldn't be a problem, as it would still drive off your transmission (or transfer case if 4x4). But I don't know how easy it would be to get the rest of the bells and whistles working. Might take some careful wire tracing and splicing as the harnesses wouldn't match up like a 92+ truck with the electronic speedo and same generation dash as the 7.3 Powerstroke trucks.




