Bravada pinion seal

Hi all, I'm new to the site and have a some questions re-guarding the replacement of the rear diff pinion seal on an 1993 oldsmobile bravada. 1)What does the nut need to be torqued to and do I need a new one.2)Do these rear ends have crush sleeves and if so do I need to replace it if I'm just doing the seal job. 3)What special tools do I needs. 4)More specifically, when do I need to measure the torque specs and in what sequence. This is my first rear end r&r so I'm kinda unsure at the moment and would like to take all the extra precautions necessary as I'm aware of all the things that might go wrong if overlook something. I do have a chilton manual but the section(s) outlining this particular area are kinda general and vague so I would appreciate any help. Also I did search and found a 96 bravada diff service fsm, I was wondering if this is the same as a 93?
Thanks again and sorry for a lengthy first post.