68 Barracuda Alternator upgrade.

The ammeter conversion thread.......... Read all of it, as it covers several cluster styles.

PLEASE don't try and use the original ammeter


Ammeter to Voltmeter...who does it?

If you research some of the 72-ish / newer C barges they went to external shunt meters, which essentially used the harness itself for a shunt. You can download factory service manuals free, from MyMopar

Even "Ma" knew the ammeter wiring was inadequate as back then there was "fleet/ taxi/ police" wiring that was used for optional 65A alternators. The factory bulkhead wires were clipped, and new ones run directly through dedicated grommets in the firewall. This too can be documented in the 69--72ish factory manuals in the wiring section.