time consuming, thats about the hardest part except for getting your hands in there to undo the bolts that hold it onto the tranny
best thing i could say is- if you have never done anything like it before lay under your jeep for about 5-10 minutes to look and see how everything goes together, then when the time comes jack it up and put jack stands under BOTH axles (make sure they are very secure) undo front and rear drivelines, speedometer cable, use a good sized floor jack to support the transmission or something sturdy (being careful not to dent the pan)
the shape of the t-case makes it difficult to use a floor jack to support it while you are removing it so it is best to leave it bolted to the crossmember and place the jack underneath the crossmember then undo the bolts securing it to the tranny, and after its all loose you will have to remove the 4 bolts holding the crossmember on then drop the floor jack down very slowly, just enough the clear the bolts for the crossmember and then comes the tricky part, it is easier to have a pretty strong guy helping you cause he will have to balance the t-case on the jack while you slide it back away from the tranny about 3 inches and then it will be free enough to lower the rest of the way down
i think i covered everything, but who knows i slip sometimes, hope this helped a little