Driveshaft, axles, getting a floor jack under there to balance the 3rd member on etc.We are not talking a Ford 9". In the case of those (and a lot of Toyota diffs) then it is a very simple third member removal. Only difference is having to remove the driveshaft.
Let's not go down this rabbit hole since the Jeep does have a simple cover. Just wanted to point out that there are some other cases where removal is not that simple.