I don’t think you can get the two long bolts out of the bottom of the ZF case (which hold the bottom cover on) without pulling the ZF, or at least raising it so high that those bolts clear the frame rails……
Then, once you have the ZF out, your access is really restricted if you are trying to work on the ring gear and carrier only through the bottom of box
it’s 10x easier to work on things with the carrier out than in.
Rocky