I AM NOT LOOKING FOR THE 2 FLAT CONNECTOR ADAPTER! that is for 1984-1993
My radio looks like this but with chrome buttons

The Connectors on my radio look like this:

The only normal plug is for the antenna.
The Ground Wire hooks to a bolt on the radio itself

No one has a harness for this thing. So I will need to improvise. All I can tell so far with the help of a Haines wiring diagram and the help of an old school mechanic is that the weird double round thing is power. One constant 12v the other is either dim with lights or ignition power. These two wires are red and orange.
I have 5 other wires connecting to the square connector and 1 black wire that goes from the top pin to the bottom pin in the last row.

These are just a best guess:
2 wires are left speaker 2 others are right speaker.
Then there is one extra wire in the square plug we have no idea what it is for.

I will have proper pictures in a few days

Also once this whole mess is figured out I will post the wiring diagram for everyone

 

OK So here is what i have got.
RED WIRE - Always on 12v
ORANGE WIRE - Ignition power 12v

Square connector: Has six pins not 8
so yes this is way less complicated then i thought. Once I get the parts I need I will document the process for others who do not want to cut off the stock connector

 

I've gone to the junkyard and cut the pigtails off of another car, as you said any Chrysler vehicles from 84-ish up and using the wiring diagram of the car that donated the pigtails make my own harness while leaving the original one lay behind the dash for future consideration. I did my 78 sport fury like that. I needed FM radio, am only was getting old.

 

Looks like this guy never came back, so hoping someone can confirm this for me, in the post above the OP mentions that red = always on 12v, and orange = switch ignition 12v. I am trying to install a radio into my 81 truck and am working around wiring that the PO somewhat butchered. However, the main thing I am stuck on is this one connector, in my case the PO had the red wire connected to a radio he had installed, but only the red and not the orange. Testing the stereo, with the ignition off, the radio is off, ignition on, radio is on. Which would indicate to me that in fact the red wire is switched 12v and therefore the orange would be constant 12v.

But... I cannot find anything confirming that. While the behavior of the radio I am removing would indicate that to be true, I don't want to wire the new one up that way just in case it is backwards.

Does anyone know?

 

Get yourself a cheap volt meter. Might even be able to 'rent' one from your local parts store. Test voltages on both wires under both conditions. That will give you a definitive answer.

 

It's always good to remember that you specifically bought a test light for this truck.... red wire, definitely switched, orange wire constant 12v. Red wire only illuminates when the key is on, orange illuminates with the key not even in the ignition.

 

That works.

 

Well, shoot the orange wire is no good. I suspect the orange is actually the illumination wire. I connected everything up and no power to the head unit, verified again that both red and orange have power, checked the ground (ran a test ground direct to the battery) and still nothing. Disconnected the orange wire and ran a test straight to the positive on the battery and the radio came on, so now I am trying to figure out where to get 12V constant under the dash, or just run direct to the battery.

 

Test wires coming off the ignition switch.... also check what size fuse they run thru.

 

I ended up using the constant 12v for the map light, my truck does not have the light, so used a multimeter to check the voltage and found the middle terminal to be constant power. A quick test with wires twisted together to confirm all was good and then permanent crimp + heat shrink.