Bindings are way too big. I understand they changed things for 2013, but on the 2012s I fit a 7.5 boot into a medium binding (their chart says too small but it fit well) and got it centered.
Bindings too big. Board too wide. You mentioned REI? Return that shit. With the binding that big you're never going to get it centered. For christs sake your boot doesn't even reach the end of the toe ramp.
Get a normal width board, a medium binding and then see how it centers.
With the binding so large, and the inability to move the heel cup forward, you have a boot that starts way too far back to get centered. I don't even think the old style cartels would work on centering that boot.