It will work if you wire it properly!
To prove it, I have an '85 turbo engine in my '79 300TD with a working tach (my clock/tach portion of the instruments came out of an '83 donor car) I ran all the wires thru the firewall using some scrap wires I bought somewhere. The pick up coil that senses the pulses at the crank balancer has to be a MB shielded cable, get it off a wrecked car because a new one is buck$

The only problem I ran into was finding 12 volts to power the tach. I got it off a lead that goes hot when the ign switch is "on" - thru a 2 amp fuse to be safe.
I believe all the engines use the rotating magnetic pin on the crank balancer, if you don't have that on your balancer then you will have to find a suitable balancer and swap it (not impossible but a nasty big job compared to the rest of the task!)

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!