Actually, I would like to know as well because I am getting the lumber thunking sound that bigcat described. I hate that I will have to tear the entire strut assembly out again though. I guess it should be easier now that I know what I am doing.
Is there any way to test if the problem is these without removing them? Also, would i need to get another alignment if I would install the GT500 strut mounts?
I had a clunking sound before and I found that it was the swaybar endlinks that needed some tightening up try that first. If that doesn't fix it then I would think the strut mounts have failed. Also a good rule of thumb to follow is get an alignment any time you mess with your suspension especially the struts.