Car Rear Seat Mattress Extension Plate, Portable Mattress for Sleeping, Foldable Back Seat Extender, Increase Travel Trunk Space and Car Bed Camping Space for Car, SUV, Model Y/3 (Black)

I used this - this weekend it was handy. You still have a little angle so not quite flat but you’re camping not in a hotel. Colefunmit Car Rear Seat Mattress... https://www.amazon.com/dp/B0FD46LX88?ref=ppx_pop_mob_ap_share

Used an exped megamat, there’s also these things that hang from the front seat when pushed all the way forward that cover the gap between the folded down seats and the feet well for rear seat passengers. I am 6 feet I can sleep “straight” with another person using this. I will say I plan on doing a rooftop tent though. Colefunmit Car Rear Seat Mattress... https://www.amazon.com/dp/B0FD46LX88?ref=ppx_pop_mob_ap_share