getting new xj sometime. couple questions...

In a few months (hopefully) I'll be getting a newer xj. I think I know what I want, but I would like some opinions. I've got a 90 limited 4.5" lift. and rust up the a$$ right now.
Here we go:
91-96 4 door, I-6 HO. no power window, locks, mirrors, seats.

I think I want an ax-15 (i've got an aw4 now.) i'm not sure why i want a manual. Sell it to me. pros and cons and if i'm looking at an xj, how do i know it's the ax-15 and not the ba-10 (i think thats what the other 5 spd is)

i want the 231 t-case. what year did the input splines change? i've got an extra but it's out of an 89. also, did the output spline change?
I don't care about axles as long as it has 4wd. i've already got two d44s and a 9". but i don't want to go full width yet. (MN gets pretty picky about tires sticking to far out. and i don't want to get monster flairs.... yet.)

i'd like to have the nicer gauge package, but as far as i know, that's a fairly easy swap. i've taken mine out several times, but i think after 91 it changed to an electronic speed sensor, instead of cable.

so, there it is. tell me what you think, and try to help me decide what exactly i should be looking for.
btw: i've got no problem swapping things. as long as they're not too time consuming, this will have dd duty.

on the topic of the trans if u plan on doin serious wheeling then u'll deffinatly want the manual mainly just cause u always have the torque when u need it u don't have any automatic overdrives or anyhting messin with ur wheel spin or engine speed and in the year xj's that your looking at the most popular was the ax15 and that was by far the best transmission that came in the xj's in those years i'm very familier with the ax15 but not much with the ba10 i'm not even sur eif they were available in thoses years but i do no that they were labeled as light duty transmissions and the ax15 was labeled as medium duty (there was no heavy duty ever offord b/c it wasn't nesscery because of how light they were) but like i said i'm not very familier with tthe ba10 so i couldn't tell u how to identify it but the ax15 u can usually tell by how it was mounted on the undercarrigeto the cross member. the crossmember runs right under the t-case and a plate mounted to a rubber transmission mount on the cross memeber the plate went towards the front of the vehical then curved up and have four bolts that go into the transmission now the ba10 my be mounted like this to but i'm not sure but i no for a fact that is how the ax is mounted
i hope some of this is of help and if i were u i would put the dana 44's under it and if there for jeeps then they shouldn't stick out on u

All 91-96 4.0 manuals are the ax15. My first was an 88 with the ba10 and then I had a 92, 94, and now 96 with the ax15. The guages are real easy to swap out--you'll have to buy and swap out the oil pressure sender(by oil filter) and the coolant temp sender(back of valve cover, driver side). 96's made after May have the 29 spline axle instead of the 27 spline. A Trac-Loc is a plus. 96's also received additional NVH(noise, vibration, harshness) upgrades. 96's also have different cams(peak torque is 1000rpm lower) and bigger fuel injectors(23.2lbs). When I was looking for a replacement for my 94, it had to be a 91-96 2dr 4.0 with the ax-15, so I think you have good parameters already for what you want. Oh yeah some year in there(93 or 94) the slave cylinder was moved to the external of the bellhousing(easier to replace).

t-case spline count went from 21 to 23 spline betweeen 90 and 91. All BA-10 should have 21 spline and all AX-15 should have 23 spline.