The grommet (a metal o-ring) was used at the bottom of the turbo model strut tubes.

Also, if you used KYB struts as replacements, these have journals on the piston shaft which cause a clunk over the most minor of road roughness. Solution is to spin off the top shaft nut (underhood) and slip a couple of thick washers under it. This takes up the gap between the journal and the underside of the strut bearing.

BTW, later on I seveloped another symptom: Brake caliper drag upon backing up with a turn involved, plus a side-to-side clunk when turning.

Tightened up the caliper bolts, cleaned & lubed the brake hardware, and tightened the sway bar brackets.