OEM head unit 2001 Z3 cassette or CD?

[badgertr6]

Was the factory head unit for a 2001 Z3 with the Harman Kardon option, and the factory CD changer, a cassette player, or CD player? I want to return my Z3 to factory sound system, but need to know what BMW head unit(s) are compatible. The rest of the system(speakers, amps, CD changer) are all OEM. Yes, I know the OEM system kind of sucked, but I want to return the vehicle to the factory system.

[GELewis]

CD