Hey, Jerry - Wouldn't it be interesting to call up the dealer and speak to the service technician, and tell them your story (they may or may not remember), tell them what you were told needed to be done (new engine at $28k, wiring harness, yada yada yada), and then inform them what it actually was.
I'd love to make the phone call just to see what they say...
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".