Countersunk aux longeron and mid cabin brace for rivets and screws. Drilled rear angle for mounting a couple of small nutplates, and c/s for NAS rivets. Cleaned up mounting angles and shot them with primer. After the primer dried, I attached the nutplates with the squeezer. Riveted on the front mounting angle. This was a bit of challenge—could not see the bottom end of the rivet—tried using a mirror, but ran out of hands to hold everything. So, just centered the squeezer on the flush side and mashed the rivet—came out just fine. Attached the rear angle with flush screws. Ready to locate and drill holes in the mid cabin cover for the Andair trim ring.