Southern Yellow Pine board planks were used originally in production Chevrolet pickup bed floors all the way through about 1980. To remain faithful to the original: Treated pinewood planks, rip cut (three different widths) and grooved to accommodate the metal bed strips. The pinewood bed floor was originally painted Black in early models, later trucks were painted same body color on the assembly line (cutoff date not known). Didn't take long with regular use for the paint to wear through, revealing the bare pine grain.
Above technique was used in 1985 on my 1955.1 3100. The bed floor paint is long gone; however the treated pinewood floor has held up and weathered well; still in use today. It's a working truck.
