I came across this and thought it must be of general interest but could not see an appropriate pigeon hole

 

https://www.space4dreams.com/p/297/floor-leveling-for-skoda-roomster

Its a project that I am about to start, I was going to make one of the wooden boxes with the forward hinged flap for a raised reclining position, this has given me some other thoughts about an interim measure.

 

If you look at the photos you will see that the top part of the 2 main mattresses are totally unsupported, unacceptable given the price and the little extra it would have cost them to do it properly.

I once (or twice) slept in a 2CV but I preferred an Eriba Puck L caravan.

I did find this interesting, but have not studied it in any detail, yet!