American Motors: Voltmeter, amc gremlin x, altenator

Question
Kevin! THANK YOU FOR THE QUICK RESPONSE! Yeah right now my voltmeter is hooked up with the power running through the guage from one post to the other, but one side is supposed to be grounded correct? this is confusing me a little, but im hoping that instead of having to replace my altenator, i will just have to do some simple wiring. If you could go through the steps of hooking the voltmeter up that would be great. The wire that runs to my voltmeter comes off of the positive battery side of the solenoid, but im not sure where it runs to after the guage, any idea? is this correct even? i didnt hook the last guage set up.

Thanks again Kevin....so far so good! Keep up the good work!
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Followup To

Question -
I have a 1973 AMC Gremlin X. My problem is my voltmeter guage reads 12volts with the car not running, but climbs to 18volts! when running. The guage is new, although it did have an ammeter hooked up before, it is now a voltmeter. will this guage change from ammeter to voltmeter(voltmeter is hooked up the same as ammeter was on old guage) be why i am getting such a strange reading? Or is it maybe my altenator needs replacing? I could really use your help with this, it has been puzzling me for some time now.
Thanks Kevin!
Kris

Answer -
Kris,
A Voltmeter is NOT connected the same way as an Ammeter. A Voltmeter is hooked in parellel, an Ammeter is connected in Series. If your Voltmeter is connected correctly, it should read 12 Volts with the engine not running, and should not go above 14.5 Volts with the engine running. Before condeming the alternator, you should have the charging system tested using a charging system tester. i.e. Sun VAT 40 or 70. Let me know if you are not sure on how to hook up your Voltmeter.
Kevin

Answer
Kris,
A Voltmeter requires only two wires. A wire running from the battery positvive to the meter, as on the solenoid cable that runs to the (+) side of the battery. The other is a wire that runs to chassis ground from the meter, as on a metal bracket under the dash. If you hook it up backwards, the needle will read oposite. With the engine running, you should read around 14.5 Volts. If you needle swings the other way, your wires could be crossed at the meter.
Kevin