1991 Honda Accord Seatbelt

I was a victum of random vandelism. Please help me repair the damage. A brick was thrown through my window and also smashed driver's seat belt receptor. I found an auto recycler who will sell me the part for cheap, But how do I get the old one off and put the new one on?

Also, I would like to replace the inside door handle as the plastic is cracked and the handle has to held at a certain

angle to get the door to open. I can get a part for $24 from the dealer, but how do I get the old one off and the new one on?