Disconnet the drive shaft at the rear only, leave it connected to your t-case and just move it to the side.

Take the nut off (companion flange) You will notice the nut has been staked, just bend that stake out so you can turn the nut...you will know what I am taking about when you see the nut.

Remove the seal, a screw driver and hammer work great...don't worry about destroying the seal, its already bad and your replacing it anyway. Just don't dig the screw driver into the housing, just the seal.

Replace the seal. It will fit tight, use a small block of wood to tap it back in flush.

Replace the nut and re-stake it...you can re-use the same nut you took off or replace it, its up to you.

Replace your drive shaft....and your done.

Oh and there is no need to drain your diff to do this either. A little gear oil will come out when you pull the seal, just have a rag for the drips.

The first time you do this may take a little longer than 30 min. Maybe 35 minutes..