What has changed is the cheap. Alternators are so cheap and they sell them at such high amperage, your stock 1950 gauge would need some serious shunting. People buy them because inverters work so well with them. 80 amps is entry level when dealing with inverters.
I DID like what he said about how to shunt them properly. With knowing the original resistance, if you have a meter that can read that low, its easy to put the proper value of shunt material across the terminals for the particular amperage alternator. Done correctly, with the proper gauge wire and the proper value shunt, there is virtually no worry about fire, but its something to think about.
I may go with two like you said Dave, not sure yet. The voltmeter is so easy to hook up just about anywhere. Just gotta find a place to put it. And the Tach too!
You could put two discrete terminals in the downfacing part of the dash (underneath). The kind of terminals used for test points. One black, the other red. Nobody would see them and you could just carry around a multimeter in those drawers under the seat pedestal. Whenever you suspect a problem, you can hook up the multimeter.
