Newbie, looking for help

looking for decent running B2600i engine, or suggestions on rebuild kits/long blocks. Also wondering (i have a 91 2wd cab plus) if i found 4wd powertrain would all components be easily transferrable into 2wd chassis? (frame is basically same i am guessing). thanks

You would need to swap the oil pans as the 4x4 is different to accommodate the front differential. The rest of the engine parts should be the same as far as swapping in a good engine.

Other differences...
I have seen a different style PS reservoir on 4x4s before, but have also seen the same reservoir as 2wd trucks. I'm pretty sure the pumps are the same.
Radiator fan shroud is difference on 4x4 vs 2wd.
Some models used different AC compressors (and mounts). Direct mount versus ear mount. But that's not 2wd vs 4x4 specific.

I may have an engine available for you, but it will be in Florida.