You should be fine with 8 ga. wire on that light load. (You'll probably never go near the full current draw.) For a while, I had a 600W amp with just an 8 ga. power wire and it was fine. Just be sure to fuse the 8 ga. adequately near the battery. (Btw, how'd you get the 60 amps? Is that the sum of the fuses on the amps?) If you do decide to upgrade your wiring, a decent 4 ga. kit can be found at WalMart.