What's your impressions of the CPT shell so far? Is that a 60" cabover? Do you have any photos of your securing method?
I have only had the camper for two days. So far, I really like it, it is a bit daunting with all of the bareness and "whiteness" inside but that is what I wanted, a blank sheet of paper. I had considerable input with their engineers into the design which was fun. OH inside bed area is 53x80 inches. CPT is an industrial manufacturer so everything has a solid, minimalist, no nonsense feel to it, what I was after.
I used a "tethered swivel pulley" system in order to avoid needing access to the front tiedown point on the camper when loaded. Using two pulleys per side and an adjustment at the back, the load on each tiedown is equalized. I used the factory inbox tiedown points, GM tells me they are good for 600 lbs. each. With a camper this light and my style of off-road driving, I feel comfortable using them, others might not.
I'll post some pictures later. You basically have a separate tie down system on each side of the camper. On each side, I tethered each of the 2 swivel pulleys to the corner truck bed tiedown loops, using quick links. Using pre-measured SS aircraft/ATV winch type cable, attach one end to the front tiedown point on the camper, bring it down and around the front pulley and take it back to the rear pulley, running the cable under the pulley and then up to the back tiedown point on the camper. Initially, I just used turn buckles to secure and adjust it for the highway trip home. However, in order not to over stress tiedown points, I believe you need to build in some stretch to any camper tiedown system.
So at the back, I will be either using a modified spring loaded camper tiedown or more likely, as a recovering climber, I want to experiment with putting in a section of nylon 1" hollow climbing webbing or even 11 mm rope. There are some great YouTube videos of the Italians testing these products to failure, this stuff is tough!! Of course, ratchets with flat synthetic webbing would work just as well and are being used by lots of folks now.