A couple of pieces of extrusion are now hinge brackets (2 down, 6 more to go). I don’t have a band saw, and snips are a bit too weak, but I had success with a hack saw. The corner was simply rounded with files.

The skeleton for this half has been completely assembled: drilled out, deburred, primed, riveted. I’ve also attached the bottom skin to it and enlarged the holes to A4.