After doing several of them, you might get it done in a day, first time plan on 2-3 days. You need some special tools too. Here is a quick and dirty short cut: be sure the bolts inside the case are tight, then goop silicone RTV on the area that is leaking (clean with solvent first). There is no pressure helping itto leak, so you are just preventing a gravity leak. Actually, the bolts should be tight as they used sealer on the threads beginning about 1996, so you could try just the RTV first. It might look bad, but you really can't see it after the truck is together.