First thought off of the top of my head. The wires going to the ammeter have been switched.
The needle should be going negative (discharge), during starting.

If the needle is going full positive (charge) all the time, while the engine running, then this is a different symptom.

Last edited by buoymaker; 07/02/2022 4:38 PM.
"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."