Radio replacement?

You are making my head spin.

"but sum it up the wire only gets power when I turn the key (which it will turn the key wire does not get any power"

If you never have twelve volts on the yellow/black wire, and fuse # 11, has no voltage on either side, the likely suspect is the ignition switch. The part of it that feeds the radio's switched twelve volts also feeds the delay wiper circuit, the rear wiper and washer circuit, and the power windows, if you have those. If all of those systems are out too, head to the ignition switch's connector. You will find twelve volts on the yellow wire feeding it. You are supposed to get twelve volts on its black/light green wire when switched to the "run" or "accessory" positions.

Somewhere along the line fuse 11 is blown, it is making poor contact in its socket, or that yellow/black wire is cut. If the delayed wipers work, that proves the ignition switch is okay.

I will be back tomorrow to see how you are doing.

You are overlooking something very basic. You have to have 12 volts all the time on the light green/yellow wire, and there must be 12 volts on the yellow/black when the ignition switch is on. If the interior lights work, the light green/yellow circuit has to be okay. If you are finding 0 volts all over, check what you're using for ground for your meter or test light. On a lot of Ford products you will see a metal bar running along the bottom of the dash assembly, but that bar does not actually bolt to the body, so it cannot be used for any ground circuits.

We often need to know the engine size to get the right wiring diagrams and parts lists, but not in this case.

Oh; that adds another dimension to this sad story. I used to tell my students it was not proper to run a new wire to solve a problem. The defect in the old wire must be found because whatever happened to it is likely to happen to the others in that harness. Common things are a harness fell down and was rubbing on the sharp edge of a metal bracket, it fell onto hot exhaust parts, or a screw got run through that harness. How long will it be before the same thing happens to the next wires in that harness, and where will your customer be on a dark Saturday night when he's broke down on the side of the road?

In this case we can assume the defect was caused by operator error, and while a hot wire will melt the insulation on adjacent wires, we are probably safe in assuming if no other damage has shown up in those other wires this far, they will likely be okay. This would be an appropriate time to run a new power wire for your radio.

The light green/yellow wire is for the radio's memory circuit so it is always live. My question is if the yellow/black switched power wire got red hot, why did the fuse not blow? That is just a 15-amp fuse. 15 amps will not turn that wire red hot.

Touching two wires with the same voltage will not hurt anything. All that can happen is one of the circuits will not turn off when it should.

Sorry that the diagrams reproduced too small to read.

Left front speaker is orange/light green and light blue/white.
Left rear is pink/light green and tan/yellow.
Right front is white/light green and dark green/orange.
Right rear is orange/red and black/white.