NP 249 xfer case questions

I posted here a couple of weeks back about my neighbor's 93 JGC with an AW4 transmission problem. At the time he cooked his trans and replaced it with an AW4 out of a '90 Cherokee. It wouldn't move with the replacement trans but It sounded like you could hear the trans shifting if you put it in drive and accelerated slowly. It would grind if you tried to put it in park while running. It turns out that the output shaft of the '90 trans is a smaller diameter than the '93 trans, so it was never engaging the transfer case. My question is, can the input on the NP 249 transfer case be changed to match the smaller output shaft on the earlier AW4 or do I need to find a different Xfer case? I'd like to put the NP 231 in place of the 249 if making the 249 work is impossible. Would there be any major problems to doing this? Any other suggestions?

If I remember correctly, the 231 can be swapped in for the 242. Don't think it will work in place of the 249. The 242 and 231 are both part time, selectable 4wd systems. The 249 is a full time system.

I read a couple of posts from www.jeephorizons.com from swamp boy where he went from 249 - 242 blew up the 242 and went to a 231 had todo input swap might check it out can be done.