Panel - Sliding canopy
Here are a few pictures of behind the panel for a sliding canopy. The first picture is the back of the panel looking up, showing the three ribs, one in the centre and two that are 9 inches either side. They are about 2 inches deep where they contact the panel so you cannot mount anything in the panel at these places.
The second picture is of the sub-panel where you can see the three ribs bisect about one third of the way down.
The third pic is from the pilot seat without the top skin on.