I have personally done this 3 times.
You don't need a spring compressor....in fact the MB manual has 2 options.....one using a cradle and one using a compressor. I used the cradle option. Without the cradle!
You simply need to get the front end in the air, floor jack under the control arm, remove stab links and shock nuts and then remove the eccentric bolts. lower the table and the spring falls out with absolutely no tension.
Subframe Gusset Reinforcement and Bushing Replacement - Benzworld.org - Mercedes-Benz Discussion Forum
Spring Replacement: Lowering The Front End - Benzworld.org - Mercedes-Benz Discussion Forum
Good write up with many pics.