Make a sketch of a camper shell. Design the frame with a "scoop," or overhang, above the cab. This makes the vehicle aerodynamic and provides better gas mileage. Build the framing in two sections -- lower and upper. Determine the total height for the camper -- for example 48 inches or higher to avoid having to stoop when entering the camper. Use pressure-treated 2-by-4-inch boards to construct the framing.
Make the length of the lower wall the same as the length of the truck bed. Cut four 2-by-4- inch planks for the top and bottom plates. Use a measuring tape to mark off 16 inches on the boards. Go back and mark 3/4-inch marks on each side of the 16-inch marks. These lines help properly position the vertical studs.
Cut the 2-by-4-inch studs to the appropriate length. Make the total height of the lower wall section high enough to allow the bottom of the top wall section to sit a minimum of 2 inches above the cab. This prevents the cab and camper shell from rubbing when the components flex when traveling.
Erect the upper wall sections. Cut two bottom plates the length of the truck bed to the front end of the scoop. Determine the angle of the scoop, which hinges on the degree of angle of the 2-by-4-inch piece that attaches to the bottom plate of the top wall section and angles back to the top plate. The final length of the top plates depends on this angle. Cut the top plates and the studs, and assemble the upper wall sections.
Secure the two wall sections together. Predrill the holes, and use 3-inch deck screws to join the sections. Place the wall section on a fiberglass panel; trace the outline of the wall section. Follow the manufacturer's instruction for attaching the fiberglass panel to the framing. Install windows in the panels as designed.
Build the framing for the front wall, which fits behind the cab and between the outside walls. Install the fiberglass panel. Make the width of the panel wide enough to cover the outside edges of the side wall framing. Cut the height of the fiberglass panel to fit under the 2-by-4 inch boards that extend over the cab. Use 2-by-4 boards to frame the window opening in the wall section. Follow the manufacturer's instructions for the opening size and installation methods. Measure the bottom of the cabover section and cut a piece of fiberglass panel.
Cut the 2-by-6-inch roofing components. Assemble the camper shell with the assistance of two helpers. Place each wall section in the truck bed but do not move the components to the front just yet. Lay the 2-by-6 inch boards flat and screw them in place. Secure the front walls to the side wall sections. Push the shell to the front of the bed. Secure the shell to the caper. Drill three 3/8-inch holes through the bottom plates and truck bed for each side wall section. Make two holes in the bottom plate for the front wall. Insert ¼ -by-2 1/2 inch bolts and secure with lock washers and nuts.
