Today was sort of a frustrating day. I returned to work on the rear seat attach hinges in earnest, only to have my progress thwarted by an apparent error on the drawings. Dwg 32 shows the hinges on the bottom of the rear seat-back. These attach the seat-back to the floor. The drawing shows the hinge eyes at the outboard ends of the hinges. Dwg 29, meanwhile, shows the other half of the hinges, the halves mounted to the floor. On this drawing, the left hinge segment is clearly drawn with the hinge eyes also at the outboard ends of the hinges. This clearly won't work, as the hinge eyes will line up and prevent the seat from being mounted. I decided to lay the hinges aside and call Van's tomorrow for verification before I drill any holes.
Next, I picked up the F-810A Aft Bulkhead and took some measurements. It's exactly 7/16" too narrow, leaving a nearly quarter-inch gap from the fuselage skin on either side. A couple of days ago, I called Van's and told them about the fit of the part, and was essentially told: "That's impossible -- these are CNC-cut parts. And besides, we've never heard of this before." (Several other builders I've talked to have also notified Van's of identical problems with the F-810A, so the denial was kind of odd.)
I narrowed my options to three. I'll either a). split the bulkhead in two (vertically), then spread the two pieces apart slightly and rivet on a connector, b). cut off some of the flanges and fabricate new ones, bent to match the existing skin curve, or c). fabricate a completely new aft bulkhead from scratch. I'm leaning toward the latter option.
Finally, I decided to do something productive. I installed three nutplates in each of the aft rear floorboard connectors. I also drilled and clecoed the stiffeners in the "forward aft" floor skins. The manual says not to install these stiffeners yet, but that's because they're assuming each floorboard will be in one piece. Since my smaller floorboards can easily be installed without bending them at all, the stiffeners are going on