Any AX-4 or AX-5 will go right in. they are all 21 spline outputs, so your t-case will need to be that also. if you want a 242 then you'll need an early one, 87-90ish, because after that they were all 23 spline.
the spline counts for 8.25s are 27 and 29. 29 spline are found in 97+ XJs (along side the dana 35, so look before buying). don't know how many 8.35s came in 4.10 gears, but I would start with car-part.com :thumbsup: