Let me throw in my 2 cents here.
Harry, you are writing about a tag on your engine. To the best of my knowledge there were no tags on the engine - unless it is a "Tauschaggregat" (replacement device) tag. This tag means it is a replacement engine replaced by MB. If it is so, maybe Clasic Centre can help determine what was on the tag and engine number, etc. What I know from, I think the Tech Manual, is that the US dealers often stamped the engine number on the block after this kind of replacement.
But what came to my mind is that when the European car was brought to America, it must have probably been re-done for emissions control so that you could drive it in America. That change might have involved even pistons (that's what i judge from EPC), camshaft and other components. Maybe after such work the "Tuaschaggregat" tag might also have been placed on the block.
Could this be correct?
My car is an Euro car bought in Dortmund. Some time after that it travelled to the US. Then it was brought back from the US to Poland and I bought it. It has the "Tauschaggregat" tag. I was sure that the engine was just replaced at some stage, but I think it might be after the emissions set up only, not necessarily a breakdown.
I am attaching the picture of the tag with engine number covered - for reference to what you may be looking for.