It's not as confusing if you use the numbers properly. Since you stated 210.606 and since there exists a 210.606 chassis one can never know.
Your title shows you own a 1996 E300D which is a 210.020 car. But by the weirdest of numerical conincidences does have a 606 motor. Thus the question, do you really have a E220 CDI 210.606 car?
But if you have a 210.020 car these would be the tentioning parts:
Bosch Master, ASE Master, L1
33 years MB technician