Hello Nutone expert. I have a circa 1993 nutone cassette/ radio master unit and 7 speakers. My friend just gave me a newer model...IM-3303 and 4 matching speakers. I would like to use the new speakers with the new master and also continue to use some of the model IS-419 old speakers with the new master as well. Is this possible? Also, how do I wire the new speakers in the old rough holes? The old wires are red,red stripe,black,black stripe,and orange,orange stripe. The newer ones call for blue/copper,grey/center,and blue/stripe silver. Any help would be appreciated. Thanks. Joe R.