Welcome to Complete Off Road for a large gear and
locker selection at great prices. Jeepz now has a vendor forum so check them out also.
Does your '89 see a lot of street time? I'd consider welding the rear spider gears (lincoln
locker) as it's cheap and reliable. There's actually less stress on the rear with it welded than with an auto locker that will lock/unlock with a lot of shear force.
I ran my '95 for years with the front and rear stock axles welded, never a problem. Used a manual disconnect on the front axle so I can switch to 3wd to help on tight trail turns.