some autozones have those pins hanging up on the shelf. ive done two fox doors and a sn-95 door.
the sn95 door was HEAVYYYYYYYYYY I had to rig up my engine crane to support the door while it was disconnected. not too terribly hard. theres little bronze bushings that go in the door hinge. its important that the bushings dont turn with the door... they need to fit tight into the hinge assembly. the only movement should be the pin against the bushing. if the bushings fit in loose, you need to find a way to get them tight into the hinge or they will rub against the hinge and destroy themselves and you will be right back in the same boat. if I remember correctly, on the sn-95 theres a big bolt that you get to from inside the car to remove the bottom hinge from the car. if you decide you need to take the bottom hinge off, mark it with a pen or something so that it goes back in the same location, otherwise the door will be off a bit and may chip paint when you close it. its all just trial and error, but you can get your doors to open and close like butter if it has never been in a wreck.
There may be a worn bushing in the drivetrain causing a little bit play that leads to a clunking sound when you shift. More than likely it is a bushing in the rear end that needs to be replaced.