I was inspired by the woody in my build, I am using a 4:3 21.4 inch screen, worked out pretty well bezel wise. The problem with wise screens, htough, is the big top and bottom bezels. To compensate, I would make the admin panel right below the screen a little larger, and bring the marquee down a few inches. The marquee area is, what 6 inches high? Make it 9 or nine, that will eat up a few more inches of bezel. It will look weird with no bezel on the sides and 6 inch bezels on the top and bottom.
40 inches will be cramped. I think my panel is 34 inches wide or something like that...