I shall repeat, if you wait too long to repair and cannot turn the key, you will go from a simple lock cylinder replacement to having to drill it out. You make no mention of the steering wheel lock not releasing so for now that part is ok. Brian Carlton is dead on regarding replacement. The ignition switch has no interlock with the shifter unlike most American cars. With the key removed and the steering wheel locked, you can move the shifter to any position. You MUST get the ket to no. 1 position. WD40 sprayed in, compressed air using a small nozzle, anything that would free up the tumblers allowing key rotation. Good Luck!

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81 300CD (sold) 1972 280 SEL 4.5 (sold) 1966 250 S 4 spd (sold) 1974 450 SL (sold) 86 BMW 325ES (sold), 1973 280C (sold) 1988 300 SE.