Dave, as JB has said on another thread, checking the backlash on the trans axle crown gear gives us a level of confidence about the rebuild durability. Pull the bell housing off. Check the backlash ( If not within specs.proceed). I made my own bearing retaining nut tool using a piece of 2 /1/2 in. od pipe with the notches ground out. I marked the existing position of the nut with a sharpie, followed the manual to remove nut. My backlash was within specs, so I just replaced the seal and replaced the nuts back to the mark. Good luck. Ps, frost up here last night.