Can any one help me out with some ideas where to begin ..recently had my 1940 Chevy 1/2 ton rewired adding dash lights fog lights and a spot light. .. I’m running a single wire alternator which I recently had tested and passed all the tests .. after running truck for a couple miles using lights and fog lights battery goes completely dead ...per altenator guy the altenator is pushing out 85amps .. I’m running a smaller type battery that was just fine before rewire .. only fog lights and dash lights and spot light we’re added on rewire .. I checked the voltage at idle speed at battery and it’s getting 13 volts I checked the voltage on wire connecting to altenator and it’s 36volts can’t understand why I would be getting 36volts .. I did disconnect the ground terminal from battery and connected a volt meter to measure and with one lead on the ground post of battery and other to ground wire off the tranny I measure 10 volts .. is this right ?