As far as I know, the only difference in 99-02 front axle housings is that the manual transmission GVs have steel housings, and the autos have aluminum. They interchange with no problems....many have done it to get rid of the cheesy aluminum one. Somebody correct me if I'm wrong. Also, if you're having a problem with the seal, there is an updated design.....of course manual hubs are the best solution!
From one of my earlier posts:
....I just had this seal done when I got my 5.12 gears installed. There are two OEM Suzuki part numbers for that seal:
09283-35008 was the original design, and has been superceded by the new part #09283-35052. I would try to get the newer design. I'm assuming it is improved versus the old design. Good luck.