I had that noise on my '93 2.3 at the right rear wheel location. I had my wife take off in the car while I watched the right rear wheel and I could see and hear vibrations and movement. When I removed the right rear wheel and lifted up on the suspension, I could see play at the Sub-Frame Mount, Front. This is number 12 in your diagram.
I spent an afternoon replacing this item, (it's sold in pairs, both sides) and the noise stopped.
No problems since.

Dave

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible