I have a 07 and someone was nice enough to help me out with this recently. If you have the 6 disc changer, then I believe you can purchase the Toyota interface. DiceElectronics makes an interface (which I haven't purchased yet.) I found out they make an HD Radio interface that has iPOD functionality built in. I figured I would check on this first. When I called them about it, apparently it is going to be a while (sometime next year) before the new HD kits are available. I figured in the meantime the AUX port will work, rather than spending more money and having to tear down things twice.
http://www.diceelectronics.com/Merch...CE_IPOD_TOYOTA