1993 Premium Radio replaced, want to replace and bypass factory amp

I need help figuring out how to wire an OEM radio to an aftermarket amp with all new speaker wiring.

I recently purchased a ‘93 GT Vert that had an aftermarket radio. No sound was coming from the Pioneer radio. Factory door speakers are still there, but the dash and rears are new Pioneers. The previous owner gave me an OEM radio, but I don’t think it was the one from my car. It has the amp under the seat and 6 speakers so I assume it is a unique to ‘93 Premium system. I bought a Mach 460 radio from a ‘95 Mustang that I want to use with an aftermarket amp. I’m not sure where to get the speaker output wires to pass to a line output converter. Is there an aftermarket plug for the 6 pin that I need? I assume the 8 pin blue wire from the factory amp will not be needed since I’ll be using an aftermarket amp.

Pic 1 is my factory amp
Pics 2 and 3 OEM radios. Mach 460 is on top and the one the previous owner gave me on bottom
Pic 4 is the adapter harness that the Pioneer deck was using
Pic 5 is my dash harnesses

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When I unhacked a harness in a “New” Beetle, the import repair shop printed out the part of the wiring diagram (4 or 5 pages) for me to see what wires went where for the radio, amp, woofer and monitoring lines for the computer and freakin dash module. They did not want to mess with it, and were glad to print the pages out for both levels of stock stereo.

That’s what you need for the newer radio, and for the car if you want to use any existing wiring. I hope someone can do that for you and that you are good with schematic diagrams.
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The bottom radio that the previous owner will only work if you rip out all the amp wiring and just plug the body harness into the radio.

Here’s the amp, with the wiring.


Here are the plugs at the end of the amp. The two on the left plug into the radio, and the two on the right plug into the body harness.

You can take all this out, or tuck it out of the way. The two plugs left for the body harness would plug into the bottom radio and you should have sound.

But you don’t want that.

You can use this metra harness, but you’ll only use one plug that connects to the speakers. This will come from your amp. The other plug can connect direct to your radio.

You’ll have to take the hacked up 8-pin you have and connect that to your amp. Wiring diagrams above

This thread might be a good FYI for you, but it’s not quite what you are working on, but it might show you a few things

The Mach 460 will turn on, but no sound. Maybe because I haven’t gotten my shorting plug yet or maybe the aftermarket deck and speakers burned out the OEM amp.

It looks like the metra harness is for using the factory amp. I’m removing my factory amp and putting a new class D amp in the same location. If hacking the 8 pin blue wire will not give me preamp inputs for a line output converter, I’ll guess I’ll have to go with and aftermarket HU. I haven’t cut my blue wire in the car yet, but that would be easier than patching that short blue cable I have and running a new 8 wire cable.

This looks like it would work:
Sorry I didn’t Post the harness

Metra 1985-2004 Ford Lincoln Mercury Non Premium Sound Wiring Harness, Standard Packaging https://a.co/d/3UgAi95

You would use one of these to connect your amplifier to the OEM body harness. One is speaker, the other power. You’d only use the speaker plug assuming you are using factory wiring for the speakers.