Ahhh! The carpet stretching. I want to eat dinner.
This looks better than I thought. I put my Thermarest in there and laid down with the rear door closed. Sorry, no pics of that. I think that this will work for real.
All I need now is to thoroughly test drive with it in there. It doesn't budge on the street. It seems really steady. I will show some more pics of the tie down possibilities later.