I appears that Nero 5.5 can see both drives, and will allow me to burn Audio CDs on the Yamaha (but not on on the Sony -- This may be due to the way I wired them up when I installed them; I remember setting up the Sony to be the reader, and the Yamaha to be the burner, due to its better speed). So maybe the problem is with CLEAN!
I just downloaded the update to CLEAN!3.2, so we'll see if that makes a difference.
Again, any additional feedback, experience or advice is appreciated.