Heres what it should look like installed to ammeter face. I clipped the plastic needle leaving a short stub and super glued the ammeter needle on. I am going to run a denso alternator with a fault light so I modded mine for a red fault light. Pic 2 you remove the red shaded area so the needle can swing.
Pic 3 shows 2 wires coming out of the back of the panel. The red jumper feeds the volt gage off the 12v gage feed. I ended up eliminating the black wire and ran the volt gage ground lug right to the metal gage housing. I shimmed both gage studs to get the right height. On the negative stud I used steel washers, and sanded the gage housing to bare metal in that spot to help a ground.
On the positive stud side, I enlarged the gage housing hole and used a plastic grommet from the sun gage mounting hardware to insulate it, and stacked up plastic washers on both inside and outside of the gage housing on the positive stud to insulate it from shorting to ground.
The pot on the back you can fine tune we here you want the needle to sit at 13.5V. I set mine slightly above half on the gage.
Take your ammeter feed wires and bolt them together and cover them with either tape, or shrink tubing and shove em back into the harness. I used 2 layers of shrink tubing on mine
I hope this helps you with what you need to do
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