Appreciate all the info, fellas.
The Pontiac 8.2" axles were fairly easy - - I had some room behind the axle retainer plate to work and I was able to cut a deep gouge in the lock ring with a cutoff tool. Split it with the chisel and it came right off. Then cut halfway through the bearing and removed the top portion of it. Finished off the inner portion by taking a chisel to it and knocking it off the axle intact.
I wanted to be extra careful as these are fairly rare forged axles for a Pontiac "Heavy Duty Saf-T-Track" 8.2" A-body rear with a nodular case. Most of the axles were cast.
For the AMC, I don't have much room to work with right now, but should be easy once I remove the hubs. Have to pick up a 1 5/16" socket today and will get it off with an impact. Will use a puller to get the hub off, then the axles should fit into my press.
Thanks!
Scott