[HAULIN' IT]

1/2" square tubing is not near strong enough, however in your video it looked like you are holding 1" tubing? Kinda hard to tell with the lens making it distorted.

Also you need to think about the span you are going across. That One foot piece around the fuel cell is NOT the same thing as going 4 feet across...Yes it may be made out of the same material, however the distance is a factor when carrying weight. The height & thickness of the material is what gives you strength in what you are doing...the width of the material is really of no concern. I do feel 1" tubing would be fine for the limited weight you are carrying & would provide a reasonable surface to put your fasteners in to hold the aluminum. I would suggest heavily painting the steel structure & the bottom of the aluminum before you attach the two. Aluminum will corrode when mounted against steel.

The area going over the rear could be made out of 1" angle due to the rigidness of the area...would still give you the vertical strength & a surface to attach your fasteners. Same thickness material would be half the weight...just a thought.

I really don't think the "modular" idea is worth the bother...It would be easier to jack up the truck than fool around removing/installing a bunch of rivets & reaching down through a hole. Much of a project (coil-over install) it would be easier to just remove the bed, Just my opinion.

Also you mentioned going to coil-overs...make sure you allow for that clearance to the backside while building your "dogbox roof", they take up more space than may be realized without having them in place. Lorne