Date registered: Jun 2007
Vehicle: '95 E300 DIESEL, '91 600SEL, '92 600SEL
Location: San Diego/USA & Belgium/Europe
Mentioned: 21 Post(s)
Quoted: 1018 Post(s)
W210s are all OBD2 cars so that pretty much makes it a different animal vs. the W124.
Check the part numbers on the ECU housing. If the number on the W210 ECU starts with 124 you're golden. If not, I would not dare install it as you might turn your car into a mobile statue.
And all W210 have full smog equipment. Not sure who told you they didn't