For my 2010 model, it's on the floor under the central console (between the driver's and the passenger's seats). Prise open the panel (nearer the front of the vehicle) using a screwdriver. Then, eject the disc and replace with the new one.
I am planning to wax my other car and thought I'd buy a car wax that would also work well with the RX 350 too. Does any one know or have a good brand of wax that they would recommend? I have never waxed a car before and would appreciate any advice. Cheers!