I'm pretty sure that plug leads to the tweeters (small speakers) inside the plastic tray. Are you installing the Mach 460 in your 'Stang? You can, but only if your car had "Premium Sound" from the factory. This factory option includes wiring behind the dash and into the doors. If you don't have Premium Sound, you're going to have to replace the wiring harness in your doors to run the Mach 460 system. From your photo, you are missing the Mach 460-specific amp, and the two-part wiring harness that leads from that amp, down the driver's side and eventually plugs into the speaker tray. You can find these missing pieces on eBay.
I'm pretty sure that plug leads to the tweeters (small speakers) inside the plastic tray. Are you installing the Mach 460 in your 'Stang? You can, but only if your car had "Premium Sound" from the factory. This factory option includes wiring behind the dash and into the doors. If you don't have Premium Sound, you're going to have to replace the wiring harness in your doors to run the Mach 460 system. From your photo, you are missing the Mach 460-specific amp, and the two-part wiring harness that leads from that amp, down the driver's side and eventually plugs into the speaker tray. You can find these missing pieces on eBay.
Thanks, I figured it out when I took out one of the speakers, it actually goes to the woofer, the ones next to the woofer go to the tweeters... That was a photo I found online and posted that shows what I was talking about, I was going to replace my speakers and hadn't removed the housing yet but was curious what that plug went to.