is it 4wd? then you need a GM transfer case, and need to address the fact that said transfer case is probably going to be passenger side drop.
I think the later model GM's are DS drop? I remember that being thrown around once. Neither here nor there, around here you will probably find 5 GM D44's for every Ford D44 anyway.
Engine swaps on their own are not terribly cheap, I bet I have $2k in mine between trans, driveshafts, exhaust, cooling, intake/carb and all the other little bits. And that is on a fairly common engines swap with a lot of the trial and error done by others.
A Ranger engine bay should swallow a small block of any color fairly well. Like I think I said before length will get you in the most trouble followed by exhaust manifold/header choices. The less mainstream the engine the fewer exhaust choices are going to be out there.
That said my experience with the offbreed GM smallblocks is they are weird. Dad has a '57 Chevy Bel-Air. "gonna get to it someday" project that has sat for the 20 years he has had it. 283 is stuck from sitting and arguably it is a monumental looking task... where do you start? Well he has a mid 60's 350 Buick sitting around and since you always hear about interchangeable GM stuff is I thought we could poke that in and once it is running and driving we could feel more inclined to do other things to keep the ball rolling. Check into it, the thing has freaky exhaust manifolds, like they dump towards the front (I wonder if it was out of a FWD), nobody makes new/different ones and the only headers you can get are $700+ longtubes. Apparently people only put Buicks in Buicks so I couldn't find anywhere if regular small block manifolds would fit. The engine looks like a freak, the dizzy is on the front and actually goes into the aluminum timing cover (that otherwise looks a lot like a Ford timing cover

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Anyway... another idea for you. You like Oldsmobile... how about building an Oldsmobile truck? Get a Chevy truck the same vintage as your engine and build a "what could have been" truck and deck it out as an Olds. I know Ford Motor Company built a Mercury truck back in the 60's... something along those lines. That is kind of what I am doing with mine, building what IMO could have been the ultimate Ranger. Most parts are +/- 5 years of the build date of the truck, so to me it is a "what could have been".
For that matter I have seen S10's with Bravada front clips too..
Anyway if you do it be sure to make a build thread and keep us posted, oddball engine swaps are interesting to watch.
