This is going to sound like weird advice but you would be wise to heed it: Take this car to a Mercedes dealer and let them do it.
This dual carb set-up has over 800 different adjustment to it. (Yes, that number is eight-hundred) You also need some rather special tools to do it right.
You might also consider dumping the carbs you have and replacing them with a new set of Weber's. Weber makes a carb set-up for this car and the Webers are easier to adjust and will make the car more fun to drive as it will respond better. They will also not cost that much more than having these carbs rebuilt and adjusted out.
Check with your dealer before going there as they may no longer do this type of work. If they don't they will likely be able to direct you to someone who can.