I have 4 terminals 1 marked ignition (that should be 12v positive right?) 1 marked batt (that should be 12v negative right) 1 marked acc (that should feed the voltage meter and anything else?) 4 goes to starter solenoid. The VOM harness has tags for the anmeter but I am assuming the same wiring is used for the voltage meter.
1-Ignition = power wire to coil or ballast resister if one is used. Power wire to volt meter. Power to any other items you wish to be powered when the switch is in the run position.
2-Battery = + 12 volts from battery positive terminal or starter's battery terminal or from the battery side (large stud) of the start solenoid if you have key start.
3-Accessory = Any electrical circuits that you want powered only with the key in the accessory position.
4-Starter = small terminal on starter solenoid.
If an amp meter is not used then you simply connect those two wires together.