You are looking at the wrong place... they connect to the female RCAs on this picture... You should def have enough... you only use 2 sets (front and rear). Not trying to be a jerk but why don't you just have an installer do it for you if you are confused? It is a nice head unit (IMO) so I'd hate to see it be wired incorrectly and broken. At the very least you could let them do the wiring then install the unit yourself. Heck you could probably mail the harness to someone on the board to get that part taken care of.
