You had the car taken to a shop. Did they just read the codes, or did you get a diagnosis that indicated the valve body and conductor plate? You say codes "59 and up.." but that's not very specific. Do you mean code P0759, Shift Solenoid B Intermittent?
You may end up throwing parts at the thing until you're blue in the face unless you can get a proper diagnosis. Someone like Steve might be able to help with a list of the actual codes (16 or 23 of them is little help) but without beig able to dive into it, that's going to be tough.
1998 C230 "Black Betty"