because they are heavy when full I like to have them placed against the front wall of the tub.
I carry 1 spare water and 1 diesel (and sometimes another one) wedged into place with a crate that holds my recovery gear
I can access these by releasing the ratchet strap that I hold them in with using the factory tie downs
I reach in through the canopy window and if I have packed well enough drag them out through the window without upsetting everything else, and can stay like that for the entire trip if I don't need the fuel or water
just make out the diesel jerry in front of the fridge and cargo box, water is beside the diesel
have it all pretty much tetris'ed into place having bought items that each complement each other