Removed and trimmed the F-705C bar doublers per plans (photo 1). While I had the doublers off, I drilled the most inboard rivet holes that hold the carry-through bar to the lower bulkhead. These holes are immediately behind the angled section of the bar doublers. I also match-drilled the F-705D bulkhead side channels to the F-705A bulkhead cross member.
I then reassembled the bar doublers and clecoed the center and outboard seat ribs to the bulkhead and trimmed the seat belt anchors to clear those ribs. I also ground a semi-circular notch in the outboard anchor of each outboard pair to clear a rivet head (photo 2).
I then fabricated the F-705G tip-up roll bar attach angles (photo 3), including the angles on the long sides, trimming the short leg to 1-3/4", rounding the outside corner to a 3/32" radius, and dressing all edges on the scotchbrite wheel. I still have only a 6-tpi blade in my band saw, and wouldn't cut the 3/16" angle well, so I ended up using my hacksaw. It was fairly slow going, but not as slow as the band saw would have been. (I wasted at least a half hour by fabricating one of these from a piece of AA6-125x2x1-1/2 - too thin and legs too short...