OK I searched all the info on this site and found some good and some WRONG info.
Today I scored a DUAL MEDIA Premium radio from a 1998 Explorer for $10! (HAS RDS) and is tagged YL2F-18C868-CC (Says 4DR Explorer Premium) The ODD thing is it still have the connector in the back for the factory sub!
I plugged it in Vs. my old radio which was a MACH radio from my 2000 (YL2F-18C868-CA) and it reads (4DR Explorer Mach) and I can definately tell a difference in that my mach radio holds back the bass to all 4 speakers where the premium model does not.
Unfortunetly I currently have the stock sub box removed and didnt get a chance to see if the premium radio would run the sub,, but I did find out that the rear controls do indeed work still with the premium radio.
The info that i find a lil fuzzy is the last 2 digits,, I hears the first letter A was audiophile B=Base and C=Premium
So the mach i would have would be a Premium MACH (CA)
and the premium radio would be Premium Premium LOL (CC)
Guess I would like to see a database put together of all the KNOWN radio codes.