you'll have to
*pull up door sill trim (access screws that hold the rear 1/4 trim)
*remove the rear seat bottom (it pulls straight up - takes some effort)
*remove rear seat backs (they overlap the rear 1/4 trim)
There's some button style retainers once you have the seats out of the way and then the interior trim pulls out - its held in with metal clips.
You can get the trim out of the way and leave the seat belt attached. Otherwise to remove the trim panel completely out, you have to unbolt the floor anchor bolt for the front seat belt.