Hello, I am new the forum and wanted to share the truth about my recent experience in installing coilovers on my unmolested, mint condition, 20,000 original miles, 2005 (W209) CLK55 AMG Convertible w/ factory AMG wheels and factory sized tires. The cars overall ride had started to get soft and sloppy over the past year, and upon inspection, the rear shocks were completely shot and needed to be replaced. Rather than just replace the rears, I decided to refresh the entire suspension, with KW V1 coilovers. I am pleased with the decision and the result. There are a lot of discussions and different threads about coil overs on the W209 CLK's, with a variety of thoughts an opinions, some was helpful, some, not so helpful, so I thought I give the forums the straight goods and the truth about the specs and part numbers to make this easy for the next guy or gal.
KW Variant 1 Coil over Kit - p/n# 10225002
Venum Wheel Accessories (hub centric wheel spacers) - p/n#253189106004 (via ebay) (10mm Front, 12mm Rear)
The re & re installation process was very straightforward, (about 1 hr labor per corner with car on a lift) however getting the proper ride height (for me) required some additional adjustments, which in the rear requires a lot more work than the fronts (to access the adjustment collar of the coil over)
The look of the car is pretty much perfect, with less than a 1 ring finger gap between top of tire and wheel well arch (top center of arch) - I am expecting it to settle 0.2" - 0.3"(as per KW tech support) so that it might be slightly less than that once it is all said and done.
Regarding the wheel spacers - they are MANDATORY with the KW coil overs. Both the 10mm (front) and 12mm (rear) is perfect. Any smaller on the front and the tire would hit the spring tower on the coil over. Any larger on the back and the tire would rub on the inside of the rear fender.
The improvement over stock is shocking! (no pun intended) I can't believe I drove around for as long as I did with the old setup. Ride is firm but compliant. Handling is greatly improved over stock, whether that is from the coil overs, the wheel spacers, or a combo of both.
I am waiting for about a week and/or another 100 miles for coil overs to settle before getting a wheel alignment, which is also mandatory.

I will not be checking this thread or loading any pictures, but again want to thank the community for all of the insights and learning and also hope that this is helpful for anyone else looking to make this much improved upgrade to their CLK.