Hi, I would imagine it would be rather challenging and very very very much. You'd likely need a ECU for SC Engine as well and possibly need to find out if new ECU will need to be synchronized with the vehicle. Also, try to research if Radiators are the same, Fuel pumps, Exhaust system, Oxygen sensors... What you want to do is tempting but massive research would need to be done. From financial perspective selling this one and buying similar year SC one would likely be less expensive and one hell of a lot less time consuming/labor intensive. If you just looking for the challenge, just try to find out as much as possible about what else is different besides Engine itself. Is Fan the same?, plumbing, wiring? Is there an Intercooler for SC in SC? is there additional cooling core for tranny needed due to higher output on SC? I mean, some time ago I replaced Clutch/Flywheel and installed Short-Throw shifter on my BMW X5, while I could perfectly leave this with my mechanic, I just wanted to see if I still got it (back in a teens I helped my father overhauling Engines and later was always maintaining my own cars, not even teens, since I was like 6, wrench in the hands and motor oil all over the clothes was a norm since I remember myself) What I am trying to say - do a good research to make sure if you go for it, you can have a pleasure of achieving the goal and not braking the bank or at least stay within planned/expected expenses.
Come to think about it - I would rather locate and bring damaged/crushed RRS from Europe which is TDV8! carry all mechanical components over and have V8 Turbodiesel - that's would be cool.
Don, sorry, I did not catch that you have a bad engine to begin with. Disregard "selling the whole truck and buying SC" as better option. Everything else still applies I guess.