74 duster electrical problems

My best guess, full fielding the alternator. Regulator not regulating alternator output. Where the short is that is causing this ? I suspect a wire got too much engine heat, melted the casing, shorted to ground. I used to see this from time to time on those 80s GM hotrods that had a huge BATT wire routed to their distributor. When that wire shorted to the intake bad things happened from engine bay to fuse box.