The volt meter should just be hooked to the ignition "on" side of the ign. switch. The terminal marked I is where this hooks up to on the meter. it must also be grounded. the terminal marked S on the back of the guage is not used and should be insulated/covered/taped ect. An Amp meter is a different story and requires alot of heavy guage wire and is run inline with charging system. R.B.
I sit corrected. Mine still has an amp meter. :notam: But not for long.....