I purchased my 90 560 SEL in Knoxville. Prior to purchase I took it to Jarek's car service on Kingston Pike to have him check it out.
I recommend you do the same.

He works on Mercedes only and when I lived in Knoxville several clients told me that he was "the man to see."

On my vehicle he repaired my radiator instead of replacing it. This saved me about $400. As he said, "When you work on cars in a communist country, you can't get parts, so you learn how to fix them."

Good luck.

Todd