Originally Posted by Alastair

Forget it! Be Cheaper And more practical for you to Import a Proper diesel car version!

EVERY electronic device, ALL the wiring,--in fact, practically everything would need to be changed over.
--Things like the electronic dashboard, the Transmission with all its electronics, All 'body' electronics ABS, Climate, ARB and whatever else its got etc....

The 'Gasser' and Diesels are made on completely different production-lines. There are huge differences.
Mercedes use different wiring-looms for practically every vehicle, nothing much is similar between the two subject vehicles.

All the electronics communicate by CAN-BUS, and if something is missing/wrong then the system either shuts down (No Start) or goes into limp-home. All the electronics 'black-boxes' are 'coded'

Dont waste your time and money trying to convert a 'late' Gasser to CDi--Pointless! Guys have tried putting CDi into different vehicles, Ive never heard of a successful transplant yet,--Except the Blutec W201 190 that Mercedes-Benz themselves made.....

ONLY option would be a stand-alone engine computer that will also comm up with the existing electronics, as far as I know--such a device does not exist.

You would have MUCH more luck in using the earlier OM.606 engine, at least That can be made to run Without electronics,--but you will still have all the trans and body-electronics to worry about--without the engine-ECU they would all shut-down....