[Rev]

I have a '66 Mustang with a stock amp guage (no need for a sending unit). It reads from slightly to the right of center to about 3/4 to the right depending on how much charge is needed as determined by the voltage regulator. I do also have a volt meter (Auto Meter) that tells me the state of charge for my battery. It also has no sending unit but is wired directly to the + terminal post on my solenoid connection under the hood. It reads from 11 to 15 volts depending on the altinator rpm.

Hope this helps a littlle.

Rev