Lift the phone connector up slightly. Connector should be dangling between the radio module and the amplifier bracket
Connect the Bimmernav.com Bluetooth upgrade harness to this connector.
If you can not easily find this connector, you can simply lift up the spare tire cover and easily remove the black plastic cover by removing the plastic nuts and the rear "luggage tie downs" shown removed in this picture. Once the nuts are removed you can swing the cover out of place.