the problem with using older software is you also get old school graphics. i returned my lexus and now i have a 2008 Toyota Tundra. It has the same navigation software as your 2008 GS's. The only way i could find of over riding it was with a "navigation pulse generator" there is a gentelman on the tundra forum that custom makes em for a fee. Basically its a little black box thats hooked up with a switch. When i want to use the on screen commands, i flip the switch and the device begins sending pulses to the navigation. It tells the computer that the car is in park. Works flawlessly.