I went from a Mazda 5 speed to an A4LD years ago in my 88 BII
I too wanted the auto for towing and 4x4ing, I also believed the A4LD is a good transmission, getting a really bad wrap for whats actually a poor rebuild and installation (front pump seal especially).
from Ford and when rebuilt properly its not a bad transmission, keep it cool and it can have a full service life
However it is definatley a light duty transmission in a 4500# SUV and today there are far better options for your 4.0L
If you can live with 3 speeds the BUILT C5/4 is your absolute best option for a 4x4 rig
There are adapters (I think you can still get them) that allow the use of a full size auto trans behind your V6, but for many like myself, this becomes alot of power loss for the OHV and why not just use the V8 in front of it? similar time and money invested
If you decde the a4ld is a good choice for you, its not a difficult conversion, you will just need parts from a auto truck similar year as yours, and you will have to add 3-4 wires from your new auto computer to your transmission
Kick down cable, brake pedal assembly, clutch pos switch bypass, auto computer, trans wiring harness, starter, cooler, radiator, floor/column shifter will all be needed.
I used parts from a 93 explorer and a 88 bii for my conversion, even a floor shifter from a 84 bronco II to shift the A4LD
I went through 2 A4LD's in my BII before I pulled it and went V8, the second A4LD built by Transwerx in So Cal is still going strong in rangerx's explorer sport I believe
I also towed a 19" bayliner from CO to CA sitting on 33's and daily drove as well as wheeled the heck out of my bii with the a4ld, only the first one let me down, and I didnt competely kill it but it was acting up enough to get a replacement from transwerx, the second unit was stout, it stayed cool and shifted firm, even abused