It might fit, but you would need to be sure the contact rings, and airbag would also match up and work....
I would think that it is possible, but you might not be able to use a 2000 r129. but my steering wheel in my 1992 300CE is the same as in my dad's 1994 R129 sl600 so thats why it might be possible that it would fit, but whether it will have the contacts function is another story...
'92 300CE - Sold
2004 C240 - C7 Wheels
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.