['68OrangeSunshine]

The original boards in my '68 C/10 Stepside are 54 years old. When I bought the truck in 1973, the original owner had kept a spare battery in the bed -- passenger side rear. That area had already rotted and he'd tacked on a 2' x 2' aluminum patch over it.
I usually put a fresh sheet of 4' x 8' plywood in the bed and saw off the excess. They last about 5 years in the desert. I've tried linseed oil, diluted. Spar varnish. Urethane. Nothing. They all last about the same. A couple of years ago I was clearing out a resort ballroom of flooring samples from a tile and carpet convention. I was tempted to build up a deck of faux wood planks, all paralled with board joints at places. Looked real, until the sun started warping the linoleum underneath the photo-similated woodlook.
A full scale redecking is in order, but it costs a bunch.