...I have Not experienced this 'Maxing' out of the Electrical Gauges. But, I can tell you that most all underdash and other grounds are grounded on a stud that is located WAY up under the dash on the Drivers' side (Left Knee). Practically where the 'A' piller would connect to the ChassisWork. You'll have to lay on your back (first lay down something clean to lay on)and use a flashlight to see it. No less than 9-10 wires are grounded here, on My '74L. Some owners have reported cleaning and tightening the contact points and nut, has helped. If you find that the Nut is Loose? This may be one cause of Your Problem. Good-Luck with it!...
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