I paid for a Trail Kitchens King Charles, but I ain't seen it yet...guess I'll have to update later.
Last year or so, and for the time being, I use MTM ammo cases, one larger one for general utensils and cooking stuff, the other for food, and the smaller green one has random larger items like 1lb propane tanks:
I use plano 1719 cases. They fit easily under the Garvin rack, even with the Partner stove and Blue ridge overland bag on top of them, its actually like a glove. I use the Partner stand and block off plate (prep area), the plate easily fits under the stove in the BROG bag, the stand I tie into the rear of the garvin rack, with the action packer totes, I found it easily uses the wasted space and does so efficiently.
In this photo you can see the 22" partner on the plano case. For $20 its a hard setup to beat with this plano cases. You can see the patner stand wrapped against the garvin markings in the green canvas bag.
Here are two photos of a chuckbox made by my father in 1965 when I was 15. It was designed to fit between the fender wells of our '54 Willys CJ-3B. It is still in use and currently resides in my '46 Bantam T3-C trailer: