76 duster gauges not working

Adding a little more info about you're wiring.
The ignition switch wiring under the dash has two separate connectors.
The red and black wires have their own plastic connector.
According to the factory wiring diagram one black wire with white strip and one red wire with white strip go to the ammeter.
There are more fusible links on the 76 model than earlier years.
Should become clearer when you receive a wiring diagram.
An example of the ignition switch connectors.
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