1965 Dart Charging System Question

Alternator vs. Battery
This is the trick to understanding the main circuit.
The car has two power sources. Current flows from whichever one has the highest voltage. (unless there is really high resistance in a ground or route)

The battery and alternator feeds join with the wires to the various circuits at a welded splice.
We can think of this junction as the primary power distribution point.
From this distribution point, power can go to the headlight switch, the fuse box, and the key switch.
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