An ammeter bypass certainly makes sense. I am using a Dakota Digital conversion to my instrument cluster (a 66 Barracuda cluster) which uses a voltmeter. I am also not using the 65 Dart underdash harness but a modified 80-83 Mirada harness in which I am using an added solid lug in the bulkhead connector - 2 go directly to the Mirada ignition switch (using a Mirada steering column) and the other directly to the headlight switch. My underhood harness is also modified with headlight relays and fuses to protect the relays, alternator wiring and the 3 hot wires going to the aforementioned 3 solid lugs. I upgraded my alternator output wiring in size and routed it directly to my junction box which is also tied to a lead from the Positive battery cable. Hope it makes sense.