I've been working on my M101A1 for the last year, modifying it to make it easier to tow behind my Jeep TJ. I know there are some purists out there that would cringe at the sight of the removal heavy cast lunette. I mostly need the trailer to haul things, but I would like to camp with it on occasion. So, I too need any camping accessories to come off and store someplace else.
I originally thought about getting some trampoline material ($60/yard x115" long) and sewing up the perimeter with nylon webbing and loops to make a flexible top to sleep on. I really don't want to resort to buying an M101 top bows and cover, as they would make the trailer (in my opinion) too tall for the Jeep, and more than cumbersome to drive. Looking out the rear window of the Jeep with two car seats in the back is bad enough.
I like your idea of using a tonneau cover from a Ford F-250, and making a pop-up out of it. Adding a shelf on top of the wheel wells would make for a lot of storage space without sacrificing legroom, and actually add a little usable floorspace since the wheel wells are out of the way.
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