An amp gauge typically has a shunt built into it that divides the current flow thru it. If you drive more amps thru it than it's rated for, it would just peg the meter, with a large percentage of the current flowing thru the shunt. That shouldn't harm the meter unless you're running 1000 amps thru it.
Basically, an ammeter is a voltmeter set up to measure voltage drop across the shunt. (That's probably TMI, so you can ignore that last item.)
I sent you a PM with my e-mail if you'd like to send me the picture of your current (
) meter, and I can add it to your post.
