The manual says to drill a small hole in the bumper shock prior to discarding it. That hole allows the fluid to drain out. and will allow the shock to collapse. Once drained, simply push it in and spot weld it!! My 450 SL had one front shock that was empty, every time I washed it, I would have to pull that side back out away from the body.

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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.