I don't haul anything and being able to tell acquaintances I can't help when they want to borrow my truck and me because their washer/ATV/fridge/etc. won't fit will be heart warming. lol!
Just saw this! Very timely!
https://expeditionportal.com/trucksu...-buyers-guide/
I realize this thread is getting old, but I'm curious, did you ever grab a box? What did you end up getting? I saw the https://www.highwayproducts.com/ referral which is one I would have suggested, but there are lots of good options I think (as you discovered).
I also was reading about your desire to be able to quickly access the box without going in and out of the bed--wondered if you'd ever looked into a sliding truck bed? Not sure if it would make sense, but just a thought.
Hope you got something worked out.
And late...but here's the link to a slideout bed I was thinking of (couple of versions):
XT2000 truck bed slide
XT4000 truck bed slide