I am glad to see Randall back on board.
I have a slightly different point of view regarding an alternator. I too like the ammeter because it is a real-time indicator. A voltmeter or ammeter is only a gauge, and the usefulness of either is dependent upon what it shows, as well as what is perceived from what it is showing.
True, if an alternator is installed, some re-wiring is required (assuming the old regulator will no longer be used to control the alternator output). Also true, if a higher output alternator is used, eventually the stock ammeter will probably fail (assuming it has been wired to see an excess current than which it was rated).
I have installed a 30a alternator and have not changed to a voltmeter, nor shunted my ammeter. I see no need for a higher output alternator -actually the generator was capable of meeting the normal electrical demands -when it worked. My (halogen) headlights draw less power than the stock bulbs. My electric cooling fan does take some power, but only runs with the engine running (and alternator producing). My cell phone charger and GPS are the biggest power "hogs" added. Combined they have not blown a 10a fuse.
The ammeter is showing current going to or from the battery, not the cumulative electrical load. The only time the ammeter should be showing an excessive charge, is after an excessive drain -like after continued cranking, but not starting. (And even then, my alternator is not expected to produce much more than 30a.) After a normal engine start, my ammeter goes a little higher than when the generator was installed, but it is not pegged. Otherwise, it's about the same. (If I had a failing battery I might see the re-charge take longer or at a higher rate.) I will not have another generator failure, because my alternator is a more rugged design. I do not anticipate an ammeter failure, or see a need to change anything.
My ammeter and alternator work fine for me.