'Popping off' the seatback for a look takes one second - but only once you have mastered the technique.
See the two 'latch' shaped objects ringed in red?
The technique is:
- sit in the back seat;
- put both your thumbs on where you think the back ends of those two 'latches' are;
- hook your fingers over the top edge of the seatback:
- press forwards with your thumbs and pull back on the top edge to release those two latches.
You are trying to bend the top of the seatback so that the front end of those two latches are lifted and release from the seat frame.
If there is any significant resistance, you aren't doing it right - this does not require any wrenching (or indeed hoiking), it's a finesse operation! Just pulling indiscriminately can break the seatback, so fiddle about until it clicks open like the secret door in a horror movie.