I am trying to replace a deteriorated seat belt in my daughter's 94 850 wagon. I know that the leather seat needs to be removed from the frame to get access to the bolt holding on the belt retract mechanism, but I'm having difficulties accomplishing this part. I need directions for either removing the seat back from the car frame so I can get to the zipper and remove the upholstery from the bottom of the seat up to the retract mechanism, or (preferably) remove the head rest and roll the leather down from the top.