Check or replace the wire between the coil and the distributor. When the dizzy moves from the vacuum advance operating, there could be broken strands inside the wire that interrupt the primary current from the coil to the points. I like to use high-flex wire like voltmeter leads are made from.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!