For the tongue jack, I carry a 6x6x16, a 2x6x16, and a 4x4x24, all PT pine. These reside in the truck bed. The 6x6 has a handle. I reserve a spot by the tailgate for them, so if dirty or wet doesn’t matter.
For the stabilizers, I have 3 sets of legos in their separate bags and 4 pieces of 1/2” treated plywood. The legos live in the pass through. If these get wet or dirty, I just brush off and put back in the bag. I’ll clean them at home if necessary. The plywood goes in a milk crate with the Andersen type levelers in the truck bed.
I happen to like Rubbermaid totes. I have 4 that fit perfectly in the pass through. Electric, water, miscellaneous, and sewer fittings and supports. These are on driver’s side.
Regular chocks and X-chocks go in a drywall bucket in the truck bed.
The 4x4 is longer so it can support our flagpole.