I realized that I had made four identical brackets when I should have made two left side brackets and two right side brackets. So I laid out and fabricated the two right side brackets (in the foreground). The two extra left side brackets will be destined for the scrap pile.

Then I made the first of the mating brackets. Note that since the end flange of this bracket will attach to the outboard floor rib and that rib is not parallel with the centerline of the fuselage that I had to mark the bend lines so that they're not quite perpendicular to the bottom flange. It's about 1/16 inch of non-perpendicularity over the length of the end flange.