Those two panels that you see are only covering up the view of the shaft. They were temporary and stuck in place when the wings were open to cover it. You can tell that they are just stuck in there (with tape?) because they aren’t parallel to the inner wing surface.
So the pic with the...
Scott Janish, who goes by sjanish here, I think, did offer and cast up some for me. I had loaned him a sheet to do that a couple of years ago. Maybe contact him first ModelBuilder.
He gave me some castings, but none could quite get it as thin as the original sheets.