Hi Mike and welcome to the forum! I've attached a link to one of our site's DIY tech articles on the W211 shock replacement if you need a guide for the process. Post a Comment just below the article with your retrofit question and our master tech should be able to shed some light on if this is doable. Hope this helps and best of luck!

Mercedes-Benz W211 Rear Coil Spring Replacement (2003-2009) E320, E500, E55 | Pelican Parts DIY Maintenance Article


-Dmitry