This is the type I had on 3 different 1 ton dualy pick-up trucks. I had the same topper on all 3 trucks. I finally gave it away when we got a fifth wheel.
I had the ladder rack also, which was fantastic for hauling our canoe and the side panels with the 2 shelves were great for hauling the canoe out-riggers,paddles, life jackets, and other supplies we carried for the canoe. One side was dedicated to the canoe, the other side was dedicated for travel trailer set-up...like boards for leveling, chocks, electric cords, ropes, tools, everything else.
That left the bed of the truck completely empty, except for bringing along the blue tote, water containers, firewood, the sewer hoses, garden hoses, a 7 foot step ladder (my bed was 8 feet long), an air compressor, and a bunch of other stuff.
The only problem was with the ladder rack. It made the truck too tall to fit in the garage. When we got a bit too old to handle the canoe, I removed the ladder rack and it fit inside the garage then.
Click here to take you to the web site for the "commercial" truck caps. I wouldn't do it any other way again, if I needed another truck cap. But, with a 5er, it's just not practical. Those things are heavy and take 2 or 3 people to remove them. So, once it was in place, it NEVER left the truck until the day we traded the truck(s) for a new one.
Good luck!