Car wont start unless door is open

Welp. The entire dash is currently out of the car including ammeter. We pulled it and fixed a few problems behind the dash and it has been easier to work on.
We currently have the the two wires that go to the ammeter vice gripped.

Of course careful not to touch ground
OK. You can still check the battery voltage with key in run.
We can assume for now that the current is around 5amps.

The ring terminals are usually for #10 studs. If you get a 10-24 or 10-32 bolt you can free your visegrips. :)

Later when you get through this part of the puzzle, we can come back to the ammeter itself. If its the studs are corroded, its probably better to replace than repair.