Ok some of you know the deal on my rig, but if not here is the quick run down. Got a 91 MJ, its got a 96 AX-15 and 231 going in as we speak, as well as a 97 d30 front an 87 xj 44 rear. I have an opportunity to pick up the 231 from the same XJ that the front axle came from. It has a HD SYE already installed. Is there any compatibility issues to look out for, as far as T-case shifter linkage, trans compatibility, Speed-odometer compatibility, ect?? I should mention that the donor 97 XJ has an AW4...which is what the case was mounted to originally. thanks -J

Only real concern you would have would be case to tranny spline count. Since you have have so many mixed and matched parts Im not gonna rack my noodle figureing it out, but note that some were 21 spline and some 23 spline.

Speedo shouldnt cause any issues, shift linkage is all the same as well.

Make sure the splines match and bolt it up. Good luck.

AX-15 and AW-4 should both be 23 spline. There are 3 different lengths if input shaft I know of.

Here is all the info you will need with regard to input gears......

http://www.novak-adapt.com/knowledge/np_nvg_input_gears.htm