Nope, nope & nope, my original thinking was correct...it is a cassette with a lock ring. Perhaps early gen. Shimano, it is set down into the cassette similar to the way a freewheel looks. Local LBS struggled a little, which made me feel good, then brought out a three foot wrench welded to a spindled remove head, with chain whip, - BAM! I guess 20+ years will lock one of those suckers in pretty tight.

Again, thanks to all who contributed, and it feels good to say something positive about my LBS.