As you can see, I hooked a crow bar into the pocket of the bracket on the right side of the axle. After you remove the top end of the right shock this will allow the axle tube to drop a bit lower. Undoing the left axle will relieve as much pressure from the spring as is possible. Make sure you support each axle before you release the shock absorber.
Loosen the right side screw that holds the bracket to the axle but do not remove it. Loosen the left side screw and apply pressure to the bar to keep the spring under tension as you go. Once you have the screw removed slowly release the pressure on the spring until it's free.
No need to use spring compressors or anything fancy. Quick easy way to do this job. I'm convinced that MB designed it so that it could be done this way.
Note: having the fuel out makes this job a lot easier.