Start on the fuse by drawing a reference line through the locations of the center line of the stab. be sure to bring the front of the line forward of F9.

Using a 1/2" piece of sharpened brass tubing, carefully bore out the hole for the stab tube. Note the angles. only go in half way from one side, and half way from the other. When you're finished, wrap a piece of 150 grit sandpaper around the stab tube itself (not the socket) and sand the hole until the socket fits nicely. If it's a little sloppy, that's fine, we'll fill it during installation.

Insert the center piece of socket in the hole, and lay your root rib in place. line up the rib so the center lines match (and you have effectively 0 incidence) and drill the hole for the adjuster pin. Flip the plane over and do the same for the other side.

When you're done, put the pin in place and tack glue it.