The EU4 engine was built from September 2003.
I've seen suggestions that the EGR valve can be cleaned and disabled on the EU3 engine, but if going to the trouble to remove it for cleaning, surely simply not putting it back (and using a suitable pipe to replace it) is a better idea? I'm not sure what error codes this might raise, or if some sort of 'disable' configuration would still be required.
The EU4 engine had much more stringent emissions controls and the EGR valve is different; it has some sort of electronic interface. It can still be deleted/removed, but obviously there is a little more to consider before starting that process.
There's an option for each here.
A cheaper option is to remove the vacuum pipe and stick a golf tee in it. If the engine is an EU3 it's kind of job done; if its EU4 what ever you do will raise the EML, but that can be mapped out. For me though, I'd prefer to do the job properly.
Incidentally, the EU3 and EU4 injectors for the M47TUD20 are different and have to be coded; the EU3 injectors use a 6-digit code, the EU4s have a 7-digit code.