Try disconnecting and plugging the vacuum advance line at the distributor and revving the engine with the advance disabled. If the problem goes away, find the open or short circuit between the distributor housing and the condenser, and/or replace the wire between the coil (-) terminal and the side of the distributor. You might be chasing an electrical gremlin by working on the carburetor- - - -which can be VERY frustrating!
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!