Fusible link?

Thanks for these detailed responses Guys
Starting to make sense now.
Previous owner did Ameter bypass and added Volt gauge /also i just did the Crackedback headlight relay harness—- huge difference in lighting
I’m going to pull Brake booster and valve cover to provide access to Bulkhead soon and clean terminals
I am having Voltage drop somewhere in harness I believe based on symptoms/ pulsing from 13.5 to 15 Volts - it DOES settle at 14 Volts with steady Highway cruising
Alternator and VR recently replaced and added dedicated ground to VR
Anyway gotta check all connections for corrosion
Uggh the joys of owning a 67 with mostly original witing
The Bulkhead connectors look really clean and definitely not melted at all
Car spent its whole life in SOCAL