We had an RX300, and the display would be a pain. I suggest doing something like the CT200h does, or the SC460 does. Popup screen behind/above the stock screen. All the HVAC controls and menu options are are the mini computer behind that screen, so it is not as simple as tapping into wires to make it do your bidding. The other option of course is to hide it blindly and then tap into it that way.