Why is everything tricky on this car? To remove the B-pillar(the one with the seat belt directly behind the driver and passenger front doors) take off this plastic piece. It's a little sticky and sometimes looks like you're breaking it.
Remove the 14mm headed bolt and set the seatbelt aside.
Take the rubber molding off at the sides of the b-pillar all the way down to the bottom of the doors because there are clips that hold the bottom section.
Now pop loose the bottom dark gray part of the b-pillar, you may have to recline or move the seat, so that you can get to this clip
pull the light colored b-pillar from the bottom first then pop the top and pull down
You'll be fighting this clip hiding at the top:
To install just reverse removal and make sure you push in the top clip.