I drained the rear axle and pulled both axle shafts. It did not seem like I got an abnormal amount of oil out of the differential.

The good news is both axles are good and both outer axle bearings are good. The seals appear to be original (1948) and are simply worn out from use. New seals and brake shoes are on the way.

1948 Chevy 3100 Thriftmaster pickup
Old skool engine swap ('54 pass 235)
Four on the floor
12v conversion