These are of the bed, it had some panels on the front and sides. I think the front covered a fuel tank and the sides were possibly some sort of compartments that were also covers for the "tubs" being it had pretty large wheels and tires. Check out the reflection in the tail gate of the end of that compartment and the reflection of the tailgate in the compartment.
Look at the tailgate gap. Look at the gaps and fit on those panels in the corner of the bed.