I suspect that you will need one regulator per circuit; I see there are multiple lighting coils and I'd bet that they're out of phase. Do not combine these circuits as you'd basically be shorting out your coils.
Yellow wire from the stator powers the headlight high/low filaments, tail light, speedometer bulb, and the high beam bulb
Red wire from the stator powers the brake light, and the horn
Green wire from the stator is the return for both lighting circuits