Can a fixed 5th wheel hitch be used on a standard bed truck?

I towed for many years with a short bed, and used some sort of slider hitch. Best I tried was the Pullright. It's true you can get by with a standard hitch in a short bed, but I lost a rear window. A couple of years ago I went to a long bed or 8' bed. I definitely prefer the long bed, with a standard hitch. It could be you can't get by the long truck.