I had a similar problem after replacing my Bilstein struts. There was a lot of clunking on the first test drive.
I got back home, jacked up one side. If I grabbed the tire and lifted it vertically, I could feel the strut insert moving between the tower mount and the strut top mount.
The problem was that the grooved bottom of the strut insert was not fully seated at the bottom of the strut mount. So when I tapped in the roll pin, the pin did not restrain the strut insert from the bottom.
So, this is what I did:
1. Jack up car
2. Remove wheel
3 remove nut and washer from top of strut insert
4. Remove roll pin from bottom
5. Gently tap strut insert from top (threaded side in frunk) with a hammer. If you check you progress, you can watch the strut bottom groove slide into the roll pin hole and though.
6. Once finished, reverse the steps and torque appropriately.
