Thanks for the welcome and the link! So from what I've gathered from the link I need a medium length 23 spline input to mate to my post 90 aw4. As long as my 231 has the early cut, short length, wide bearing, I should be able to swap the input from my 242 into my 231. Does that sound right...
Well I eventually plan on getting a box4rox if I can get ahold of one, since it only mates with the 231, I would only have to buy one SYE instead of buying one for the 242 then buying a second when i put in the box4rox in.
So I'm finally getting back to my neglected XJ and can't quite remember some of the details for the T-case swap.
I have a NP231 with 21 spline input sitting in my garage, what needs to happen to attach this to my AW4
So far I am pretty sure I need to switch the input shaft to the 23 spline...