Hi Obermayr, nice cars, those fintails.
Last production year was 1968, so it's probably a 68 then.

Most of what bgcast says is true, if you interpret it as:
"I doubt it" = No/Not available = custom fabrication
"Probably" = Yes

As for the licensing this is really not an issue, just haven't done it yet.. costs about $220 to re-license it here in Sweden as a diesel car, it was a gasser before.

I've seen short fintails for sale here, converted both with 240D/616 and 300D/617-engines, but the latter sound really tight. Might go if you move the radiator a bit forward. Good luck with the conversion, although I wouldn't do it since the car already has a great diesel engine. Fix the starting issue and she'll be fine. 0-60 in 29 seconds, true power! lol
If you decide to convert, you'll run into three issue..
Engine mounts, don't match. You have to do custom ones.
Drive shaft, wrong length. Check out a reputable drive shaft shop before you begin the conversion.
Oil filter can, interferes with the shifter linkage IF you have the column mounted shifter.. Solution, move the oil can OR get a 200D/220D engine that has been in a W114/115-body, they have the oil can up front.

ps. sorry if I'm a bit incoherent, Rudolf Diesel just had his 150th birthday last week, and the only appropriate thing to do was to go to a 6-day party trip to Berlin, where he invented his engine.. just came back yesterday and still a bit tired.. just ask if anything remains unclear.

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Tomas, Sweden
1966 Mercedes Benz 230S with OM617.912, automatic. Disk brakes from W108
1983 Mercedes Benz 300TD grey, OM617.912 and 5-speed manual
1983 Mercedes Benz 300TD blue 7-seater, OM617.912 and 5-speed manual