I used to fire mechanics in my shop for using the "shotgun" approach for fixing a problem. Invest in a $5.00 digital multi-meter from the local parts store and figure out where the voltage loss is happening. You've got the manuals that will give you a basic idea of the ignition circuit, so start at a logical place like the ignition switch, and do some circuit tracing. I've gotten some of these old rigs running with nothing more than my girlfriend's fingernail emery board to clean up a set of oxidized points. The problem is probably very simple- - - -just don't get discouraged and start throwing parts at it by the bushel basketful.
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!