Has anyone had experience adding the Kenwood CarPortal navigation system (Kenwood - KNA-G510) to a Prius? I have a 2008 Prius without nav, but would like to find a system where I can use the stock touchscreen for navigation controls as well. Does anyone know whether the Kenwood CarPortal KNA-G510 works with the stock touchscreen? From Kenwood's website, it states, "Touchscreen control with Kenwood compatible monitors". Thanks.