Installing 2 amps need help!?

I'm about to upgrade my sound to 1 15" mofo power acoustik. A probox enclosure. And a 2000w amp I havent made up my mind on the brand, and I want to install another amp for highs/mids probably a 400w 4ch. How would I go about installing the power wire to both amps. The wire I have ran already is a 2gauge wire. What's tge best way I can power those two amps? Ps. I don't want a capacitor, I'd rather another battery if any thing.