I had an old GMC dually that I thought was going to be my RV hauler. It had an oak center overhead that mostly held some after market RV lights that didn't work. I made a new one with some late model Suburban lights, drop down dvd player for the kids, etc.

http://www.bunchobikes.com/gm22.jpg
http://www.bunchobikes.com/gm23.jpg
http://www.bunchobikes.com/gm24.jpg