How to replace 72 Duster window rollers???

I am working on a 72 Duster, and do not want to screws things up.
How do you replace the rollers on the window regulator? They look to be studded into the arms. I placed the roller in a socket and took a hammer to the pin side. I quit because it was mushrooming the pin. Is there a tool or what is your advice as to procedure?