Do I need 2 wiring harnesses for aftermarket cd player

[MustangLife]

I have 03 gt mach 460. I looked on metra online and got the part number for the factory amplifier interface harness that retains the factory amps. 70-5701 thats for 01-03 gt's. But I have 2 wiring harnesses that came out of my factory cd player. Do I need another one for the other harness.

Thanks
Josh

 

[COramprat]

Are you reusing the factory CD player?