You mentioned attempting to install the thicker fan assembly onto your 123. I did that on my 300CD and yes the grille rubs on the new fan! I loosened the hood hinge straps where they attach to the hood panel and pulled the hood forward away from the fan, the holes are already slotted. I also shimmed out the small rubber bumpers at the lower corners of the grille to keep the grille away from the fan while driving at higher speeds. I very carefully moved the hood latch on the radiator support forward ever so slightly so the hood release wasn't hard to pull to release the hood. Lubed the hood latch and hood hinges well and that was 4 years ago!

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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.