I've had the same problem with my 314-8 since I got it. I did the same thing, new reg. and went over all the connections too. Same thing, pushing 16v at full power, lights off. I hooked up a multimeter to it and the voltage was right on at 14.5 or so, but the gauge was reading 16+! I haven't cooked a battery or headlights yet. This will be the third year on the batt. Maybe just an inaccurate gauge.