I did the repair on mine, and that was the one thing I was concerned about was getting it centered well. First I glued the foam to the cone, then what I did was move it in 4 directions while pushing in and listen for rubbing, and find the center of where it was quiet. Then I glued the foam to the frame in 3 spots, and put the ring on holding tight with finger, but no with screws. Then tested the cone's movement, and fudged it around to where it would move smooth. I was going to order the new old stock, but didn't know if they were all 12 years old sitting in some warehouse and would fall apart as well.