Thanks for everyone's reply. I got my car up to the mechanic without problems. It turns out that the body shop put some of the radiator hoses on BACKWARDS, and that's what caused the problem. Unbelieveable.

The mechanic drained the green crap, flushed it good, and put in the MB stuff. My car is happy and has a nice clear coolant tank again!! Thanks for everyone's help.

Take care-
Michael.