Ok voltage drop test shows .59. Voltage at the VR red (top) terminal is 14.75 and gren wire 0 with motor off key on . Running the red shows 14.75 and the green keeps cycling from 8-10.5. Amp gauge shows discharge with the lights on but never shows a charge. Volt meter on dash shows 15+ and flickers and the VOM shows 15.8 at the battery. I also noticed when you start the engine the volt meter will sit at battery voltage for a second and then climb to 15+. Just to be clear the power feed doesn't go through the amp gauge like the older trucks. Ignition switch is new and bulkhead connector shows no corrosion. Could a bad diode or something in the alternator be causing this?