From Steve Schaefer:

Knock them off carefully with a hammer. I thought Jeff would break out his Factory Service Manual. It goes into that in there. Yeah all the re-manufactured ones don't include the seals. If a seal is on a re-man junk it. It went through the acid of death cleaning process.

Make sure you get the outer as well as the inner off the old axle. My joints never leaked but I think that seal is for alot more than dust. I think it seals the gear oil as well. Once the seal is back in it should stop leaking. I think you can still drive it, just not in 4WD. There will be alot of oil still in there below the axle hole line.

See why I never did a write up, it's easy but hard at the same time.

Steve