John,

Back when I was looking for a manual transmission 300E, I saw an '86 or '87 300D five speed advertised. I did not see the car, so I don't know if it was a Euro.

I'm sure it's no surprise to you, that I would be really excited about a manual tranmission 124 car with one of those powerful diesels.

BTW, I personally would not attempt this swap unless I had the donor car setting next to the recipient. There will be many little things that you will need from the donor, that you most likely could not predict in advance.

Good luck,