Wire to Console Batteries Advice

[Normagain]

I'm thinking 2 gauge would probably be adequate if I run wires to a console battery, shouldn't be more than a ten foot run (20' round trip) if I do it going through the rigging tunnel. Is there any advantage to not running through the tunnel, chance of interference of some sort? I have the chance to run cables under the deck right now since the deck is completely off. That would add at least six feet to the round trip equation however in order to get the cables all the way to the rear corner box.