1. The upper and lower guide blocks are shown below. It is recommended that you round the edges as shown so the wing will slide by the blocks easier. You also need to counter drill to allow a 7/32” socket to fit in (3/8” drill bit should work),, to tighten the nut. Use a drill press to do the counter drill, it gives you more control. If you try a hand drill, it will probably go right through the block. Only counter drill deep enough for the top of the nut to be about 1/16” below the surface. This operation will leave an angled bottom with a standard bit, but it is okay for this lightly loaded part (it only has a load while folding/unfolding the wings). A modified spade bit shown below is the best choice to counter drill with. There are 2 different lengths of screws to account for the taper.
2. Install guide blocks. Screw heads should be up for the upper guide block, and down for the lower guide block.
