72 Rally 180 electrical problems HELP!

I’ve got a 72 Rally 180cc. Keeps blowing all the lights - have tested voltage and it goes between 6-30 volts. Also when I step on the brake pedal, all lights go out (when they work). Have changed all coils, checked the wiring, switches. My only idea is to get a voltage regulator… any ideas on how to fix? All my vespa freak buddies cannot be bothered with it - they say the electrics on old models are always problematic. Any suggestions would be so appreciated. Thanks!