There is a good write up in the “FAQ’s and How to” section:
https://www.fiero.nl/forum/Forum9/HTML/000007.htmlI just purchased some from Rodney and replaced mine.
The only additional note I can add is the ball joint press is designed to crank from the bottom when removing the ball joints. If you are up on jackstands in the garage like I was there isn’t enough clearance for the “screw in” section of the ball joint to press because it will hit the floor. I had to put a spark plug socket on top of the old ball joint to press it out and have the “screw in” section of the ball joint press at the top.