I did this on my coach. Pull out your radio and on the back there are various inputs. Look for the RCA style inputs, odds are they are the only ones since most components don't use RCA style connections any more. The Yellow one should be video, with the red and white being audio. Mine also had a lead that went from back of radio to a little junction box where the all the cameras went into (rear cam, left mirror cam, right mirror cam). You could also disconnect the audio here if there is a spot to do so.
2010 Fleetwood Discovery 40X