Hi All. Am wanting to fit a Bluetooth receiver to the NIT in my 4200. It has no CD boot changer fitted so the C3 mini ISO port on the back of the NIT has no blue plug in it. My understanding is that the C3 port is where the CD changer would go so I am thinking I should be able to connect a Bluetooth receiver to the correct pins on a C3 connector, 16/17 for switched power and 18,19,20 for the ground and left and right channels. Is this correct and will that work? Any help most welcome. Thanks