Thanks sireland67. You're right. I am going to have to figure out some way to prevent damage to the wood. I've been considering a tarp. Years ago I had a custom one made for this truck that attached with Velcro. It was black with a big red and white pentastar sewed into the middle of it. Unfortunately mice had gotten to it when I had it in storage.
I never did put in any form of bedliner. My floor was always painted the red as it had come from the factory. I suppose I'll have to try to protect it. I'm planning on hauling a tool box, floor jacks, and generator when I go to the races. One concern I have is whether or not a rubber mat would trap moisture and actually ruin the wood. I guess it would work OK if I only used it as a pad while I had stuff in the back.
If the truck is outside the only way to protect the side wood would be a car cover. It would be cool to have a custom one made that fit down over the stacks.