B+ motorhomes

Gene, I get the idea of the false floor. I think my idea qualifies as a false top! If I can find a very simple bracket that fits the tv, The rest should be ok. Since the flatscreen is in the original location as the tube set, line of sight is not optimal(unless you stand up) ;) Mounting it on a hinge would allow me to adjust the angle for 'laydown' viewing.
I understand what you mean about those foldaway arms, I think that's why I want to engineer a custom mount.