The seal should point out or in, 2 different seal types on these trucks.
The clunk, as above grease the splines.
As for the output bearing, it is a brass style bushing. Unbolt the the 4-6 bolts that hold the rear most tail section of the t-case on. Then tap out the bushing and put the new one in. But it the bushing was bad, the slip yoke would be pretty gaulded as well.