I installed the floor stiffener, which was actually kind of a pain because there is no way to both see the alignment (on the bottom of the fuselage) and hold onto the stiffener (inside the fuselage). I measured and then drilled the forward most hole in the stiffener on the drill press, then clecoed it in. This locked it down a bit and I then aligned the rearmost hole. The wife leaned over the side and held the stiffener immobile (there's no place in there for a clamp) and I drilled. Then it was just a matter of drilling the holed between the ends.
The stiffener gusset goes in between the firewall and floor stiffeners. It's open on the right side, and I don't like that -- it just looks unfinished. So taking a cue from Jeff Schultz' Sonex build, I made an opposite side gusset to make a little box structure. This was easy using the first one as a template and just putting the angle on the opposite side.
The two gussets fit together over the stiffeners very well, with the right side gusset top overlapped on the left. I'm going to updrill the assembly (gussets and stiffeners) out of the airplane to make sure I get straight clean drill holes (bending over the cockpit side and doing it is not easy), and at that time I'll add a row of five rivet holes through the tops of the gusstes to lock them together.
