Jon,
Once I get done with your Alternator the guage will move. It did on mine at least. I get a good bit of deflection on my guage. I installed a 105 amp upgrade kit into the stock ALT housing and now once it's started it moves almost to the first mark.
I should probably do that to my alt, too, the electric fans are really taxing the 55amp stock alternator when the lights are on.
My "charging meter" is when I watch the headlights dim slightly at idle, then brighten again when I touch the throttle..(underdrive race pullies)