My 99 Grandby now on it's second Chev. 1/2 ton is moving enough forward with turnbuckles tight to break spot welds on front panel of truck bed. Seems new truck sheet metal is crap. Anyway, I called FWC and they have what they call "bumpers" for $ 40, I know you guys must be using something else to put down in bed in front of camper? I suppose most anything waterproof and elastic without compressing to much would work. I'm thinking it has to be about 1.5 to 2 inches thick? Maybe like these dock bumpers at Overtons $15 a piece:
http://www.overtons.com/modperl/product/details.cgi?pdesc=Dock-Edge-ProTect-Straight-Bumper&i=74432
http://www.overtons.com/modperl/product/details.cgi?pdesc=Dock-Edge-ProTect-Straight-Bumper&i=74432