I think if you want that set up you should find a good fabricator and get started. I saw someone on this site that converted a closet into a couple of bunks. I would be a little concerned about the extra weight in the slide. Why not something over the front seats? We bought an add-a-room for the outside and stack the people up there. I even thought of towing a tent trailer. Let your imagination run and do whatever you want. Keep us posted.
1992 Bounder 28T, Chevy 454, Yak Rak