S211 320CDI Avantgarde suspension

Help needed - S211 320CDI Avantgarde Sportspack suspension parts

Guys

I'm trying to identify the correct parts to fit my S211 E320CDI Avantgarde with sportspack suspension (15mm lower than standard with stiffer suspension, inverse track or wider wheels at rear, rear air suspension and I believe different steering geometry).

To date, I've already purchased and fitted the parts for the non-sportpack model (after being told that all E-classes used the same suspension parts except the AMG.

The bushes on the control arms are softer than the bushes in the control arms that I took off and the tapers on the ball joints are definitely different. The replacement ball joints work their nuts loose every few days - i guess due to movement.

I've contacted some specialists, who have given links to their on-line stores, but the listings, like the parts I've already fitted seem to relate to all 204BHB 320 CDI's (not sure what the output on my car is - need to find the logbook).

I can't be the only person that's come across this problem. Can anybody provide definitive part numbers, that are different from the standard model (really don't want to strip it out a further two more times).

Thanks

Nathan