I think to find something like that you will have to look at the companies that build them for their swing out bumpers.
A underbed mount truck box will be limited to 18" due to ground clearance.
I have not seen and top mount boxes that are tall and narrow.
Yes, I have found that out. I am looking at 18 inch boxes (now) to mount on my carrier. One on each side . Here is a pic of my carrier that I made for when we had an RV. I couldn't lift the carrier until I removed the water saturated plywood....With the boxes, I most likely will have to remove the boxes to mount the carrier on the truck.....I have checked into swingout carriers but the one I have seen in my budget are cheaply built.
While the size of this carrier limits the roads and 'ditches' I can drive over, it works for me as well as protecting the rear of the camper.
Edited by 5outta6, 21 February 2024 - 02:34 PM.
Ford F150 super crew, ATC Ocelot shell, Icom 706MKIIG, AC6GD