Had the same problem with my 66 Dart a couple months ago.At the block on your firewall under hood,there,s a blue wire with yellow tracer,get someone to hold key on in start position and wiggle that wire.That,s how I found my problem with intermitten starting problem.I cleaned the box out of corrosion and crap,fixed it!Also bypassed ammeter.Hope this helps!
I think I'll wait till day light. At my age things start to all look like a big blurr at night even with reading glasses! My 64 is in my 1 bay garage right now for a carb swap so I'll have to do it tonight first!
Thanks for the idea. That's what this site is all about!