Bulkhead bypass vs ammeter bypass

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The battery terminals are first rate. I used the military grade terminals with side studs for connecting wires. The restoration shop built power and ground wires for a 80A alternator. The alternator power does run partly through the firewall so the ammeter shows some charging, but the bulk of the power runs through a 10Gauge wire with fusible link directly to the battery. Other than the cheap Chinese alternator from O'Reilly which I want to replace, all works well.