Adding additional rear camer with Sound
I recently purchased a 2013SUnseeker 3170DS. I have read about someone adding an additional backup camera to the OEM rear view system with sound. That way I can have one pointed down at bumper for backing up against something, and the OEM as a rear view. I have searched and searched an cannot find the information.
Can anyone point me in the right direction. What camera to buy (with sound), where is the factory control center for cameras located? I am pretty technical, but just do not know where anything is. Thanks in advance!