I have been through all this too with the W126.

Buy 560SL hangars. Not only will they fit, but INSIDE (where you can't see) they have steel reinforcement rings!! You will likely never need another. The standard ones for the W126 SE/SEL/SEC are ordinary rubber, better than the donut O rings found at Autozone, Napa, Checker, etc, but worse than the 560SL hangars which will fit.

I was told this by two absolute EXPERT W126 mechanics, one in Los Angeles and by another, near the San Francisco airport.


(note: late edit: noticed that you may now only run the W123. I dont knwo for sure if the 560SL hangars fit on those.)

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)