I have a '67 Fairlane with a 351W and I've added an alternator with internal voltage control ,A/C, electric fuel pump and it's running a Duraspark ignition. All of a sudden the battery dies overnight. I've got full battery voltage with a meter between the battery positive terminal and the disconnected positive lead with everything off. The clock doesn't work. I've pulled the fuses one at a time and the voltage didn't change. I believe the only unfused hot wire goes to the ignition and I don't have any voltage at the coil with the ignition off. All lights, directionals, horn, etc. work fine. Not sure where to look next. Any advice?