Have you had any luck with this? I am extremely dissapointed with the sound system in my RX300. I just moved from a BMW 5-Series to the RX300 and it is quite a shock. I'd really like to upgrade the entire head unit and cd changer without breaking the NAV/TV/Heat LCD disply. At a minimum, I want to be able to play CD-R w/ mp3.
Any links or feedback to point me in the right direction would be great.