OK, I've done a bunch of leg work online at the parts houses by comparing parts numbers...

It looks like the lower end is identical, even the starter, which tells me the Mitsu flywheel can MOST likely be bolted right on to the crank, etc. The bearings (rods and mains) are the same, along with complete gasket set. The valvetrain appears to be the same, in as far as the valves, seals, guides, etc. Water pump is the same, along with exhaust manifold gasket. Ignition control module the same (so they share some of those components also). The one thing I cannot tell in the intake side of the heads - the gasket sets for the intakes call for a different part number, although it looks like, from the pictures, that both gaskets that actually meet the head are the same on both models. It's that third gasket that looks different, which would make sense. Camshaft: I cannot seem to find a parts house that lists the same mfger for each cam, so therefore I cannot compare the two. It would appear they are the same, but I'm not sure. Anybody got any advice? One place I found that sells reground cams had a chart and they listed the mitsu as "left side w/integral gear" and right side w/o integral gear". For the Hyundai they listed "left side w/integral gear - roller", and "right side w/o integral gear - roller". The part numbers are different. So, the 90 mitsu doesn't have roller rockers, and the 90-92 Hyundai does? What I'm interested in at this point is the timing and the cam gears. Sounds like the cam gears are the same, because they both use the same timing belt. However, the cams themselves sound like they might be different. Regardless, if the intake and everything above could be used from the mitsu, then I would think it might work out ok. The distributors listed use two different part numbers, but that could be an identical distributor with different e-plugs only. No way to know without mic'ing one and hoping for the best, I guess. I would think the distributor would need to be swapped for the mitsu ECU to work, but a guy might be able to just splice into the Hyundai plug? I really don't know.

Thought I'd share what I've learned and hoping someone will see this that's worked on both of these engines and/or done the swap.

Thanks...