Once you find a problem, everyone recognizes it. Had the same thing happen
on my Healey after I added a CB radio, wiring off the ignition screw and (of
course) not getting the new connections adequately tightened down with good
contact to the ignition wires.
The clue that Norman Nock recognized was that my Fuel gauge stopped
registering at the same time that the car stopped, hence the problem was
related to basic power. If you have an electric tach, that would produce a
60 BN7, 55 100M, 71 BGT