Starter on the M115 is on the right hand side as is the M617. The problem will be the transmissions have different shifting patterns due to the difference between the torque curves of the engines. The M617's transmission will shift much too early for the M115.

Frank Reiner says you can transfer the valve body from the gasser 123's into the diesels to make it work. Of course this means you'd need to have a separate transmission to do the swap. Seems a bit redundant though, if you already had a gasser trans why would you be installing a diesel trans into the car?

I'm in a position much like yours. I have a 300CD with a trashed engine and I have a good spare M110. Trying to decide on whether I want to use the engine I have or wait until I find a cheap trashed SD and install the entire turbo engine.

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