I did mine a while back and do remember you need to to have the car siting on it's wheels, or rear suspension loaded, before you tighten that big nut on drive shaft. That sets drive shaft static length.

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Owner of Mobil-Werks
Classic Sports and Specialty Automobile Service
1968 230 W110 +3.5 M116 & 4-Speed Manual
1985 300TDT S123
1985 500SEC C126
2022 Sprinter 3500