Pictures say more than words, but although I prefer to sleep in my tent, I found a solution to sleep in my car, without dismounting the rear seat.
I bought (for my tent) a Coleman Maxi Comfort inflatable bed, dimensions 198 x 82 x 22 cm, and this is prefect for the inside of the Grenadier!
The other thing I have are 4 "ratchet straps" and some luggage to fill some "holes".
The smaller passenger seat isn't clapped down, and serves as "side step" for the bed, therefore this solution is suitable for one person.
See the pictures. I didn't test it in real life yet.
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