Well, only one side needs 35 feet and the other 25 feet but I'm picky and want it the same so 35 feet each. I figured I'd buy additional 20 feet for future needs or in case I cut too short and mess up. I was thinking I need 12 or 10 gauge.

Axiom M60s, VP150, QS8s, EP500 -- Rotel 1075 & 1068 -- Panasonic BDT500 -- Panasonic 60S60