huh ... my 58 with a 63 amp alternator hasn't fried the ammeter, or even pegged it, and I've run the battery down good using the starter to move the truck across an intersection when it ran outta gas, then had to crank it long enough to get fuel flowing again .... maybe you guys are talking about the older AD gauges - or the wimpy gauge Stuart cites on the Austin
I've always converted my old trucks to alternators and never shunted the ammeter - no problems
Bill
