You will have to change the tri flange. the 126 uses a larger flex disc.

You will have to determine the friction pre load on the pinion nut before removing it. then when you replace the 126 flange with the 123 flange, you will now have to tighten the pinion nut to the original friction pre load torque setting.

good time to change the pinion seal as well.

here are a couple threads about the pre load.

www.peachparts.com/shopforum/showthread.php?t=233540

www.peachparts.com/shopforum/showthread.php?t=81784

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works