KenP you are correct!
Before checking the forum this morning I called the dealer and they confirmed that my car takes PS fluid, which is the bitter sweet answer. Yesterday, I went to a MB dealer to purchase hydraulic fluid and 1qt cost me $17.81! So now I have to go buy PS fluid! As I said in a prior post, the hydraulic resevoir was below the minimum line, which I suspect could be the result of another leak or neglect from the previous owner - signifying another problem. Anyone know if this is a common problem?