How are people anchoring a camper shell to the truck bed when there is also a loaded roof rack on top? Are you comfortable with just the four or six aluminum bolt/clamps? That seems like a lot of load on those points.
I do this all the time on my 3/4 ton. Loaded roof rack with six clamps. Never even gave it a thought until I read this. Full size spare goes up there. Along with whatever else.
Most shells that are set up for a rack on top are reinforced to handle the extra load, and 6 clamps are more than plenty since the load sits on the bed rails and not the clamps that simply hold the shell in place.