Hi I just bought a 2004 Toyota Avalon Grande 138k on the clock and with most of the genuine accessories i.e Spoiler and Satellite Navigation Stereo Head Unit, I want to keep the the Genuine Head Unit and was wanting to put either a separate reversing camera with dash cam and screen on the Dash Board somehow, or is there a Head Unit that fits that has all the modern connectivity features such as Reversing Camera Stereo, Bluetooth connectivity. Any suggestion or advice will be much appreciated, thanks in advance.