No power in the car

Four wires on the ammeter could be because the car was optioned with rear defroster? or something else?
It also might have come with the optional 60 amp alternator. In the photos it looks like the battery and alternator feeds could be 8 gage.
In which case the main feeds go through a grommet rather the bulkhead connector
This is from the '73 Dodge Chassis Service manual - you can download a copy from mymopar.com
The full diagrams are hard to follow, so reduce it to just the circuits you need like I did here.
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Sometimes it helps to put the color in and even size the lines. In the old tech tips they suggested making schematics by tracing with colored pencils. Whatever works for you. I often redraw stuff by hand, but it doesn't scan well.
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