Rear panel cover removal: 1. Remove the two screws. (You don't need to do anything with the gas springs.) 2. Don't bother with the seat belt cover at this point. 3. Pick a corner and start pulling straight out from the frame. You can use a bit of a rocking motion, but don't twist or pull sideways. 4. Once the cover is off, flip it down and you can open the seat belt cover. Then, fish the seat belt through and remove the cover.
Repeat for driver's side.
(Not shown) After the two side panels are out, remove the top center cover by pulling down. There are four pins holding it in place.