You're profile looks very similar to mine. All tangent curves and no flat spot on the roof. Mine is going to be 5x10.

I should note this isn't my final cabinet layout and it doesn't show my hatch hinge point. This is just the only picture I have on my phone of my profile.
Since I'm going to have a front closet wall practically as far forward as i can, I just offset it by 80" (for queen mattress length) to locate my rear wall. Then I think I tweaked both walls an inch or two forward so that I'll have enough room to put my proposed cooler on a slide out drawer front to back. I did this to minimize wasted under cabinet space. I didn't want my cooler taking up half the width of my galley.
Once I had the wall location locked down then I bumped back the hinge point a smidge so I could skin it without much material waste.
Finally, I figured based on my proposed ride height how much headroom I needed when opened. This will come into play when I need to calculate what gas struts I need and where I need them.
I enjoy the design challenge of how one thing affects another, and trying to come to a functional compromise. I bet I tweaked my design a hundred times before I made any sawdust... And I have a feeling ill probably tweak a thing or two before I'm done.
If you would like for me to share my CAD files with you for comparison, I would be glad to. Just let me know.
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