you shouldn't need the crossmember, but you may need to move yours so you may need some nutcerts.
You'll need the proper trans mount.
You'll need the bellhousing and everything in it.
You'll likely need the t-case atached.
Vent is on the top, just put a rubber hose on it and a hose clamp, run it to the top of the firewall.
You'll probably need the t-case linkage.
You'll definitly need the shifter from the AX-15, as the BA-10 shifter is way different.