Correct me if I'm wrong, here, but the output for the speedo on the 126 is electric, where it is mechanical - a cable - on the 123.

You'll also have to swap the oil filter housing and engine mounting "arms" - the cast aluminum bits which support the engine.

I've put a 126 617 into a 123, but never the other way around. BIG job!

Jay.

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On the road, currently:
'83 300D (German spec.) 168k mi. - - Wolfgang (tucked snugly away for the winter!)
'87 300D 375k mi. - finally went over to "The Dark Side"
'87 300TD 225k mi.
Cannondale 66cm CAAD5 w/Campy/Jamis Aurora
Hujsak Custom Fixie/Landshark Track Shark Custom/Ahearne Custom 29'er

hmm, sounds like i'll be selling the 126 then.

look for it on ebay if you guys are interested.

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1981 300SD, 270K, two tank wvo system
1985 300D, 288K, california version
1985 300DT wagon, 315k, broken odo

No need to sell the car. The block/head is the same in the w126/w123, except for SLS Pull both engines, swap over the non compatiple parts, and reinstall.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K