Inner and outer stem walls are attached and the ledge bottoms (cut from 10′ CDX plywood) are being fitted.
Ledge boxes are framed in and glued and screwed down to the stem walls.
Fitting the floor of the tool box or tongue box.
Ledge boxes insulated with rigid foam.
Tidying up as we go… Once insulated, the tops of the ledge boxes are closed up with more 1/2 CDX plywood. The two stem walls support a rigid cantilevered box–the support brackets aren’t even needed. I was able to stand on the edge of the box with nary a wobble.