Finally, here are pictures of my preferred mattress: the Coleman Single High QuickBed Airbed Twin (with 4D Battery Pump Combo), part # 2000010290.
Size: 73" x 38" x 8".
Now we need a picture of 2 people ON the bed in a Model S !!
Out of curiosity, I was trying to find your preferred mattress on amazon.
I found this: Amazon.com: COLEMAN COMPANY 5998M300 74x40x9.5 Twin Airbed: Sports Outdoors
For the pump why did you choose the 4D (Amazon.com: Coleman 4D Universal Quick Pump: Clothing) over say a 12V pump (Coleman 12-Volt DC QuickPump : Amazon.com : Sports Outdoors)?
Having slept in the driver seat, I can say the weight doesn't keep the HVAC on.So are you able to run the AC/heater in "sleep-in-the-car-mode" by putting something heavy on the driver's seat? There was another thread mentioning that (or buckling the seat belts), but it didn't seem completely clear that it would work in practice.
Been thinking about this for a while so I made a rough CAD drawing of the space.
View attachment 23707
I think there is a rubbermaid storage bin that you could pack with necessaries and use two or three to take up the space behind the front seats and support the foot of the bed.
I have been trying to find an inflatable mattress to take up the 3" drop but so far I have only been able to find one that could be folded in half to fit.
Umm, yeah, I use it for "camping" ...