Sorry it took me so long to get back to you.
Step 1 - Remove the bolt holding the seat belt to the floor just below the cover.
Step 2 - Remove the door sills in the front and rear doors. Use a long thin screw driver slipped under the sill at the outside edge and pry it off.
Step 3 - Remove the wind lace in the area of the cover you are removing.
Step 4 - Remove the two screws and pull the plastic piece up and away.
Step 5 - Pull down on the B-Pillow cover and it should come out easily.

The seat belt tensioners won't be a problem as long as you don't remove them. They are protected back in the B-pillar

Paul

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84 500 SEL (307,xxx miles)