Another Ammeter bypass question
Everything.
Seriously. Don't do this.
Leave it alone unless there is a good reason.
If the power feeds through the bulkhead connector have been overloaded or you're afraid of that possibility, then any or all of these will reduce the loads through those connectors:
a - run parallel wires through a firewall grommet to the ammeter studs
b. - put a terminal stud in the engine compartment and wire through the firewall like the later cars with 60/65 amp alternators.
c. install a headlight relay circuit. A plug and play version (like Crackedback makes) or permanent doesn't matter. Draw power direct from the alternator stud