Bed alignment bracket questions

I've had issues with my camper sliding around in my bed even while using the usual array of rubber mats. Not a lot of movement but enough such that the back doors of the truck can get very close to hitting the bottom of the jack feet when the doors are opened if things aren't centered correctly.

I've looked for better ways to keep the camper from moving and even posted about it in the past. What I have seen are usually wooden blocks / brackets positioned inside the bed that use the sides of the bed to stay in place and keep the camper aligned. While presumably effective enough, I don't know if I want to be putting lateral pressure on the inside of the truck bed where there isn't a lot of strength from the stamped metal.

What I want to do is hold the camper centered by tying into the truck frame directly. To that end, I've been thinking about having some aluminum brackets made that would use the existing truck bed bolts to tie to the truck frame. The simple sketch I have in mind looks like this:





Before I talk to a metal fabricator, I'd like to know what you all think about this idea. Has someone already done this? Is there something already available to purchase? Any issues I might be missing by utilizing the bed bolts?

One additional bit of information... I have to raise my camper to clear the truck roof by 2" so not shown in the images will be the foam / plywood that will give me the height I need. These brackets will be underneath the foam / plywood so the camper would not be sitting directly on top of the bottom plate of the bracket.