Got my new bed mounted yesterday. The rails were narrower on the new bed than the truck frame so I built and welded on 4 mounts per side that bolt thru the 2x4 and thru the frame. Should work fine for my application. Just need some 2x12 decking and I'm about there. Finally!

http://good-times.webshots.com/photo/2524463020101465522PqbyfM

mounts http://good-times.webshots.com/photo/2827960000101465522YnAFKa