Ideas for slide out on top of truck cover

[CanadianCoyote]

I have been thinking of adding a slide out for extras on top of the box, issue is I already have a rack with a RTT but would like to add a slide out on top of my tonneau cover. Maybe some type of molle panel to secure boxes. Anyone built one yet ?
I have to probably raise it at least 5-6 above the cover since I have a hard metal roll up

View attachment IMG_5635.jpeg
Current set up ^

Only thing I could find of what I’m looking for
Any ideas or input considered, not scared of doing some fab work if needed just don’t want to spend thousands on one of those already existing kits that might not even fit my truck and needs

 

[genocache]

Might help to think about what you want/need to put on such a structure and the changing of center of gravity, reduction of cargo capacity with GVR limits. Of course all related to where you want to go and how long. We know already that you take too much food ;^)
Someone who does soft offroading(fire roads) has different concerns than someone trying to cross Utah offroad. Lots of trade offs. With my Land Rover I have stuff in Rubbermaid Action Packers and Pelican cases. I have to unload most every night. I've learned not to overpack them so I can still lift them!!! I also made some legs for my larger cases the 1650's; NEVER BEEN DONE BEFORE! Folding legs for Pelican 1650 case

 

[Ebbs]

@PapaDave has one just above his diamondback cover and definitely puts it through it's paces, though it's mounted to the rack and not the actual tonneau cover. It's maybe an inch or two above