that which I put off several years ago. My only key was in the tool bag of another car. When I returned to retrieve my tool bag I discovered that car's rear window had shattered and my tool bag was no longer in it. If and only if you bring the car to Mercedes they will get you a matched key for $25. Unfortunately my wheel lock was quite functional, wheels hard-over, car parked in a steep driveway, completely inaccessible for a tow-truck, and bassackwards to boot. Drilling out that column lock was not an easy task for me. Currently my ignition system consists of the switch, custom key, vacuum hose cap, and hood release handle.