If you do find an E6000 but the serial number indicates it isn’t download capable, don’t disregard it until you try this easy test. It will tell you if one of its previous owners had already upgraded it to download capability.
E6000 Console Download Capability Test:
If there is a constant alarm tone and “ERROR 213” on the display, then the unit is capable of downloading.
If “ST.PATT A” and “0” display alternately, or some code other than “ERROR 213”, then the Console is fitted with an early version of firmware and will not accept downloads.
From an info sheet by Ann Croucher found in the files of one of the Yahoo Passap groups.