Back to the interior.
I built a cabinet using materials I had in my woodshop (3/4" ply for the carcass, as it was going to support the top bunk).
I used surplus laminate flooring from building our house and extended the bunks out to 24" using 3/4" ply. I cut a king size 6" ultra plush memory foam mattress into three (3) pieces using a sawsall and two (2) clamped 2x4s as a guide. We have three (3)
super comfortable bunks for a total of $160 from Amazon. I decided to do the mattress retaining trim out of cherry (I build furniture as a serious hobby).
I also repurposed a heavy post support that was installed in the M1102 and a fitting from the small air vent in the side of the shelter, added a piece of PVC as a vertical member, then fitted it all together with the cherry and purple heart table top I made. It breaks down and can be stowed easily.
I installed a second RV window on the right side to make it feel bigger. All wiring complete here, with a couple multi-gang switch panels to operate exterior lights, vent fans, and control power to the two (2) dual USB charging ports. You can see the 110v outlet on the right.