The 300SD is an electronic speedometer so you'll need a speedometer movement from an SD (or possibly other electronic speedo MB) to make it work. There is a good chance you can just remove the mechanical movement and swap in an electronic one. Many MB gauges are interchangable - for example I swapped in the tach module from a 300D into a 380SL cluster when I did my swap. It was literally a screw in proposition (now I did have to adapt the faceplate to get the readings to align, but that was just a couple of drops of epoxy.)

I'd go out to the junk yard and pull some electronic clusters and take them apart and see how they are configured. If you can find a 123 and an SD you can try try the swap right there before you buy. It may take a little tinkering, but I'll bet it could work without a whole lot of trouble.

Be aware that, while you can swap the tailcone from an electronic tranny to a manual tranny, you can't go the other way, so you're going to have to get the electronic one to work.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
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