@alsalp, you asked, WWYD? That's what I would do. You do you.
Also FWIW my process is very oversimplified, it's going to take more than just bolting on the body.
For sure the bed bolt hole spacing is the same on all of them, relative to the bed length. A 1983 short bed will bolt directly in place of a 2011 short bed, same for long beds. I seem to recall that the later beds may have a few extra mounting bolts, but you don't have to use them.
The regular cabs from 1983-1997 will directly bolt on to any regular cab frame from the same year range. 1998-2011 is the same way. The regular cabs gained 3" in length between the middle and rear cab mounts during the 1998 redesign, the frames were stretched out to match.
Extended cabs were the same length from inception to end of production. You should be able to bolt a 1983 extended cab directly onto the 1998-2011 extended cab frames. Some one actually did that build (in 2wd IIRC) on the Ranger Power Sports forum maybe 15 years ago. I don't recall the outcome other than a very nice build and they did a lot of extra custom work. Unfortunately that forum went under a long time ago and the content was lost with it.
Wernt the truck block LS's iron and the car versions alloy? Tkats what i heard anyways.
Either way an LS has alot of aluminum parts (heads, etc) and im sure a dressed 390 would be heavier. Bare block vs bare block, both being iron...i could buy the 390 being a bit lighter.
EDIT...
Quick google search tells me a bare 390 is 185lbs. A bare TRUCK LS is 210. A bare car LS is 150lbs
Couldn't tell you much about the LS except for what I said above and it seems like everyone uses them for everything. Not much different than the SBC in that regard.
Ok, so iron for iron, the LS is heavier. I would not have guessed it. That's just looking at the block though. The factory intake on the FEs weighed somewhere in the neighborhood of 80 lbs by itself, the intake on the LS is aluminum or plastic and 10 to 20 lbs. The FE heads are cast iron again while the LS got aluminum. So I suppose that the block could be heavier while getting an overall lighter engine.
Again if we're talking about a hypothetical cyclone/typhoon killer, so we're talking about a performance application where weight matters. Iron block may be preferible for putting down power numbers on a dyno or drag strip where it might be worth sacrificing the weight for strength, but I don't see that being the use case for this build or a cyclone/typhoon. As such I don't see an iron block LS being applicable to the conversation when aluminum is readily available.
Just my 2 cent. You might still be able to use a coin press somewhere for that.