I've got ryhthm....I've got muuuussic....
Well I have my 1991 OEM radio working now, thanks to the efforts of Ferrari of Seattle. Using the serial numbers from the deck, they placed some calls to Alfa and relayed the codes to me along with how to clear errors in case I mis-typed.
In short, this was a quick fix and any old/current Alfa dealer should be able to do this for you but I have to admit I'm impressed by the professionalism and patience of their service department. Considering I'm just a guy with an old Alfa all the way out in NJ it was nice they helped so much.
If the service they gave me over the phone is any indication of the service they provide to their local Italian car clientele, you folks in Seattle are very lucky.