I have a flatbed on my 65 swb with a fabricated flat bed and used the composite deck boards when I first thought about using them I got 3
boards and cut them to lengths, that gave me 6 boards and attached with self tapping flat head screws. that was 3 yrs ago,it sat outdoors
in the weather for that time. Finally got the truck done enough to install the bed about 4 months ago and picked up enough boards to finish
the floor, this was in a light gray color and I figured it would have a color difference, it did but only lasted for about 3 weeks, now you can't
see any difference, they were installed tight together and show no sign of warping or moving at all. Above all I think they will outlast any wood
product.