Interestingly, the scaling of the 16:9 version doesn't seem linear.
But here's a quick mock-up in GIMP to show what the *full* frame would look like.
This restores the extra picture at the top of the 4:3 version, and the extra picture at the sides of the 16:9 crop.
I can turn this into a video - but it's hard syncing to different video sources.