My start tumbler on my 1965 230sl was part fifty-fifty and it made it difficult to turn the key. On this vehicle, you need to eliminate every one of the 3 instruments structure the scramble, unbolt the guiding section from the floor, unbolt the coupling, fix the directing section, pull controlling segment and start lock out, unbolt start lock from guiding segments, fix start plug structure lock and you currently have your part close by. Eliminate screws from chrome bezel and you would now be able to take out your tumbler...Yes, it's a genuine work! I found that it was difficult to track down a substitution. Clearly, the tumbler for the 250 and 280 sl's is not quite the same as the one on the 230sl. From your image, you have an early model of start lock.