Just getting back to replacing the pinion seal. Got everything apart, got the old seal out, and cleaned inside thoroughly. I reinstalled the big washer up against the bearing, and pushed the new seal in without too much fuss.

I am now bolting the pinion back up. I don't have the nut torqued down to the place that it was before removal (friend is borrowing my 1-1/8" socket) quite yet. I probably need to get about 2.5 threads out the top of the nut (right now the threads are flush with the top of the nut). So everything is "snug" but not yet "tight".

When I rotate the rear wheels (off the ground) one direction, then stop and go the other way, I can see/feel the pinion "pushing out" of the pumpkin a bit. It seems like this is happening right as the teeth go from engaging in one direction to the other.

Does this always occur, as a product of the tooth profiles, or is it likely related to nut having the nut torqued down. Should I be able to feel much play at all (by hand) once everything is at final tightness?