Abstract: A novel camper-truck assembly is disclosed including mounting hardware therefor. The mounting hardware comprises a first set of rail members secured to the top surface of the truck bed side walls and a second set of rails secured to the underside of the camper top for sliding-locking engagement therewith. One of the rail members has a longitudinal rib slidably received in a slot on the second rail member and configured to secure the same together. The rib and slot have a generally wedge-shaped "dove tail" cross section. Weather seal members positioned between the top surface of the truck bed side walls and the rail members secured thereon seal against air and water leakage along the top surface of the truck bed front wall, side walls, and tailgate. Cam fasteners releasably lock the rail members against relative movement therebetween.