Just looked at my RSM's thru the peep-holes. It appears the passenger side shock-top is 3/8th to 1/2 inch closer to the frame. I'm guessing this is causing the clunking noise on that side, while I hit larger bumps. Probably a sign that the RSMs are slowly fading to its imminent death. I haven't looked under the car yet for other signs, but this is the general location of the sound I occasionally here. No signs of frame cracking or anything. This car I picked up 1 month ago is super clean (67K miles, 1 owner, BMW maintained, not even sure it ever saw rain), driven by a 60 year lady.
Any comparison data between the yellow Bilsteins and these ZSP shocks you got? I'm happy with the stock suspension. Impressive ride for sure.
2004 325Cic, ZSP, ZPP, ZCW, Owned since 12/1/12
E46 Merit Badges: OFHG, WP, ET, AT-T, ICV, CCV, Fluids (5)