I should have used the word "approximately" in my description of shunt "calibration". Jerry's right about the ammeter just being a charge/no charge indicator. Unless it's a precision ammeter (definitely not the stock one), it's little more than an "idiot gauge".

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.