The cylinder replacement was a snap! I did only one side (driver) and it took less than 30 minutes. Just a note on the removal of the windshield bow trim. I own a 1999 500SL and after I removed both black plastic latch trim covers the trim piece still would not slide rearward! I discovered two more screws! They were under the end rubber top gaskets. I had to remove the screw from each of the end rubber gaskets because there is another screw under each of those rubber end gaskets that must also be removed before the windshield bow trim will slide rearward. Still an easy job! I will check and service the system tomorrow. Thanks again to all for the help. John D