I always liked the tool box idea that do not go above the truck bed sides...
Like LAKNOX shows....
Having a larger tool just behind the truck window and then a smaller under the tail gate side would give lots of lock up space for things...
Also if it did not go above the bed rails then you could also get one of those FOLDING HARD PANELS BED COVERS and lock up the whole truck bed when not towing the fifth wheel... The FOLD-A-COVER brand would all fold up on top of the front tool box and still clear the 5th wheel hookup...
google image
Roy Ken
