And here it is.
Just picked up the frame of the seat from the engineering shop. They welded the seat in two stages. First stage was everything except for top rail and 4 small braces, on the back side, above and below the sitting surface.
The top brace is there to create an opening in the side panel of the seat for the safety belt to go through.
The bottom of the 4 legs have been coped to sit on top of the bottom longeron’s