I got all parts based on Wrathernaut's famous thread, very helpful and informative. I got a Jensen VM9424 head unit. Before I take my car apart, I think I should do the wiring first. I was able do most of the wiring except two wires which I don't know where they should go. Both wires are from the harness of my head unit. One is in brown (mute) and the other one is in green/white (reverse). Since I have used up all the wires from my Metra 70-7550 harness, I have no idea where should these two wires go to. The Metra 70-7550 does not have wires with these two color....

My car is 04 seden with no bose, no navi

 

Does your HU have a backup camera input? Maybe the green/white wire is for the HU to detect when you're in reverse gear.

 

You won't use the mute wire, and unless you have a reverse camera, that wire won't be used either.

 

thanks
so I will just leave them unused.

 

yup, either tape em off or just cut enough wire off so you wont have any issues