...and if you do a search under his user id for "chip", you get a ton of good reading:

http://www.peachparts.com/shopforum/search.php?searchid=989430

It also appears that were a service bulletin on replacing computers on E420's. Same basic engine, maybe applies to your car:

94 E420 Check Engine Light On

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".