Okay, so (1) is the 12v constant for the radio? The mustang had an aftermarket alpine head unit installed so im assuming they cut the bullet plug off to wire up the aftermarket stereo. Poor lighting, so its possible its blue with a red stripe and just be faded from time. I'm assuming I don't need the blue wire with a red stripe because the headunit doesnt require an illumination wire. If i'm wrong im sorry lol.