Last weekend I took a ride over to visit Chris(auggie91420) and in no time flat he adjusted the dwell and timing. The idle smoothed out and the backfiring and power loss seem gone. Even better, I see how to do it myself next time! Chris pointed out that my points looked new, but the cam in my dizzy is beginning to show signs of wear.
The backfiring and power loss had magically gone away for a week or so before. On the way to his place, however, it came back in a bad way, making it difficult to get up a few hills and "off the line" from stoplights, much to the chagrin of traffic behind me!
The ride home was much more enjoyable.
I have had two very brief moments of backfiring since then. Also still have the occassional stumble (mostly on decel or steady cruising RPM) but it's not too bothersome yet.
The idle RPM still seems a bit low, so I may try to find and adjust the bleed screw if it keeps up.
Thanks to those that chimed in, and to Chris who came to my aid yet again!