I put a 2" bolt with a fender washer into the back of the coupling nut, then bolted the nut through the 2x6 board to be inset into the wall form. Then I welded the fender washer to the back of the first bolt, welded a little piece of rebar onto the head of the bolt, and welded the bolt to the back of the coupling nut. My hope is that once the concrete hardens I'll be able to remove the (2nd) bolt you can't see that's holding the nut to the wood and then remove the wood, leaving the anchored nut flush with the face of the concrete and ready to allow other pieces of wood to be bolted in.