When on base camp trips in my '84 Xcab with a tall shell I take a cheap Big 5 "Two Person" tent (yeah, right!). Set up the tent and everything that doesn't need to go out on the day's exploration goes in the tent. I sleep in the rear of the truck. On point to point trips that vintage Toyota 4wd sits tall enough that I can stash the plastic boxes, that have to come out for me to sleep in the back, under the truck. Anything that might not want to get drizzled/dripped on goes in the cab.
I long debated enclosing the fenderwells with storage compartments that were vertical to the height of the top of the wells, and then sloped towards the bed rails.