Many thanks for your advice and patience. Indeed, the drat distributor, probably vacuum advance mechanism, was the cause of the jerky, sensitive throttle pedal. Swapped in a spare, all fixed.
Timing set 2200 rpm, vacuum line plugged. Idles @ 800 rpm assembled. Extra picky: just the tiniest of stumble, hesitation on hard acceleration.
Rotate distributor counter clockwise to retard ? If that might be a slight adjustment to fix hesitation.
It seems to me final timing rather has to be bump and go, as the RPM's don't stay right on 2200, the timing mark jumps around, etc.
Answered my own question with impatience. Rotate left is retard. Doing so just a dab improved throttle take off, idle, radio reception, overall disposition.
