Wagon: Question or request for pictures of the rear seat Wagon

A somewhat specific question. I got my (first) 65 Valiant wagon half disassembled. Never had a wagon before.
Now I have noticed that apparently an intermediate piece of the rear seat is missing. It is this panel to fold down. The piece can probably be re-manufactured with wood and then simply carpet over it ;) . But I should know exactly how the mechanism works and where it is screwed on. Can someone send me more detailed pictures? Both upright and folded down. Of course a video would be even better.

THE PICTURE IS AN EXAMPLE
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