Thought I'd added some more to this but I guess I backed out before it added it so here I go once again.
I couldnt find anything on anything so I figured id call the company that makes the transfer cases we all use, the parent company is called magma industries or something of the sort outta Troy Michigan but called and got a this number is no longer in service message idk beats me. So I called Novak technical support and at first guy wasn't too helpful said they don't mess with early aw4's or dodge transfer cases, but after talking for a minute he said to check the following : see if the shifter is the same or something it's not I think it's reverse of the one outta the jeep. Check the input gear(spline count is 23 for both) and overall length of the whole thing I'll get to that last ine here momentarily. Now the input shaft on the 231d is longer than the one on the jeep. But I went and crawled under the jeep to check the depth. Now this isn't a real scientific method it's snowing outside and I was in a hurry. All I had at hand was a straw from a WD-40 can. But it seems the 231d won't have any problem sealing to the aw4 I have I mean where that input gear slides in to the tranny there's definitely enough room to seal. Now on to the length. Just stick with me fellas it gets better.
Now the extension housing for the 231 off the jeep I ordered when I was looking for a main shaft for it is 4 1/8 inches long the one on the 231d is 5 5/8 inches long. And the yoke that would be going into the extension housing is 3 3/4 or so can't remember off the top of my head atm. So it got me wondering if I could do pretty much a hack n tap with out the tap. It seemed feasible if the splines run down the dodge main shaft far enough.
But yeah I screwed up������ the yoke I used to check the main shaft on the 231d I thought was a old jeep yoke I had being I have an array of misc jeep parts. Turns out it wasn't I grabbed my drive line out the back seat today to check and make sure it'd work, nope, I grabbed the drive shaft and started spinning it and it just spun around the main shaft. So now I'm back to square one. I threw the yoke I had used against the one on the drive shaft they're the same size and what not heck they even look the same at inside diameter eyeballing it. Idk maybe I bit off more than I can chew cause I wasn't really wanting to crack the case open being as I've never done it before. And I'm the walking embodiment of Murphy's Law.
Wonder if I pulled the front yoke off the other trans case and did a hack n tap and used that yoke for the rear. Sorry some of this is just me thinking out loud. Figure looking at it when it's wrote out might show me how much a bad idea it seems.