The rear seat has 2 tabs that you need to push in to free the seat, if you look under the front of them you'll see a tab about half way of the seat on each side. Push them hard with a flat driver and pull up the seats at the same time. And as far as the back you'll see about 8 screws. I think that's all you need to gain access to that panel, I did it a few years ago so I might be wrong. Lol
Taake your time its kinda tricky, don't lose it here lol.