95 possible motor swap

well, i have a 95 k1500 with a 4.3 v.6 and a 5 speed "car style" manual tranny. the problem is that the motor is starting to show its 165000 miles and it will cover any new oxygen sensor up with soot within a week of driving. it gets maybe 15 miles a gallon on the interstate and i believe it will soon go out. long story short i have a carbed 350 motor sitting in my garage from my project truck that now has a 383. the 350 is the old style two piece rear main seal style. i was wondering how much work would be involved in terms of swapping the six for the 350... i live in nebraska where they dont ever inspect cars so the whole carbed thing probably will be never noticed by anyone. what is all entailed in this swap, such as new fan shroud, bigger radiator, different motor mounts, and such and such? i know one obvious one will be the exhaust for sure...

And keep going. Alternator and power steering mount, different wiring, carb. hook up, but it can be done.