thanks man! if you notice, only that outside "rib" is in the groove and it actually helps the woofer seal itself since the foam is a little further inside the ring. Tomorrow, i am going to use a drill press and drill all the holes (so they are perfectly straight) and then basically bolt the subs to each other. The wood in between is only there to keep the surrounds from touching.
anyway, wish me luck, bandpasses are touchy and this one might fail. The design looks good on paper though.....that don't always translate to real life