I think you're on to something. I've been running into several small things the PO pulled. The car is a 69 Mach1, 351, 4spd with the tach inst. cluster (indicator light) BUT it has the factory gages mounted in place of the ashtray on the console, one of them is an ammeter. When first started the charging system reads 12.5 volts and the interior lights are steady, when you rev the engine up some the voltage jumps and the lights begin to pulse noticeably. Once the voltage jumps it stays high. The PO said the battery had been going dead but his "mechanic" had fixed it.
68 restomod coupe
67 coupe Son's