Just split the case if you are replacing the chain and other parts. Put a jack under the transmission to take the weight. Remove the belly pan, lower the quadra-trac a little to make access easier, and split the case.
The only reason to drop the entire case is for a full rebuild with bearings.
The scissor transmission lift will be a great help in removing/replacing the gears and chain. They are HEAVY. Especially bench pressing them up into place while keeping the chain where it needs to be.
I just swapped out my quadra-trac. Here's a link to the thread. http://www.jeepforum.com/forum/f8/qu...hread-1570079/