67 Barracuda Heavy Electric Load

OK. This doesn't get to the problem, but at least now we can draw a diagram of some of what is on the car.
There still is the mystery wires going in with the speedometer cable.

The reason the ammeter isn't showing charge after starting.
As discussed early, electrons flow through the back of the ammeter when the battery is charging like this.
The ammeter needle deflects (by magnetism) to show the flow.
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But in this case the current is flowing the other way, because the battery is powering the ignition, and presumably nothing else.


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Additionally with this wiring when the fan turns on and the alternator is not working, battery power to the fan will not show as discharging on the ammeter.
When the alternator is working, current to charge the battery will bypass the ammeter. The new wire to the stud on the starter relay is the shortest path.

The fan must be connected to the fan relay. Its a heavy red wire at the fan.
[edit below speculation was bassed on the understanding of two hots to the relay. reviewing the photos there is only one relay on the firewall]
One explanation for two hots to the relay is that there are actually two relays. Maybe one for headlights.
Another possibility is that one of those hots goes to the temperature switch and then is the trigger.
But more likely that comes from a key on circuit, such as J2 (which as noted in the previous thread was damaged).

The wire from the alternator output stud to the battery ought to have a fuse or a fusible link.

Here's a stock '67 with an later ECU. Modify this one in MS Paint or IRFANview to whatever you discover.
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