Removing an old aftermarket stero

1986 Dodge Ram 350. I got this recently, it came with an old pioneer system that doesn't power on. Picked up a 90s dodge unit to swap in only to find that the stock wiring is nowhere to be found on the car. Its all been replaced with the aftermarket system's wiring with built in fuses and old butt connectors. 

Here is the Pioneer unit i pulled out

All this wiring is just for the one white connector pictured above

Except for this connector which wasn't plugged into anything and I don't know where it was supposed to go

Then this is the Dodge unit and its wiring that I have

So what are my options here? The aftermarket stuff has different gauge wiring and I don't have any kind of wiring diagram for it. Does this stuff look familiar to anyone? I anticipate reinstalling the stock stuff to be quite a project, the aftermarket wiring is fully tied into the wiring harness, so I'd be fine just fixing the aftermarket unit but I can't really diagnose without a wiring diagram. 

What would you do here?

A trip to the local U-Pick will get you a look at the stock wiring. If that looks in good condition buy it.

Do you have both the plugs that plug into the back of the factory radio?  If so, you should be able to just match the wiring colors from the factory radio to the wiring colors to the truck.  If they don't match, you can use the aftermarket radio colors to figure out which wire is which.  You'll probably need to hunt down a wiring diagram from the truck to figure out the factory colors to match up to the one in the truck.  This diagram gives you an idea of what the aftermarket wire colors correspond to:

You probably won't use them all (like the amp one).  For the yellow and black one that doesn't seem to be connected to anything, does the truck have a powered antenna?  If so, that may be what that wiring is for.

-Rob

OK, looks like the yellow and black was for an amp.  This is from an '87 Dodge Ram, but manufacturers used the same color schemes for years:

-Rob

Unfortunate that the Pioneer doesn't work.  That thing is rad!  Multi-color LCD and full logic tape deck is sweet.  Might be worth opening it up to see if there is a bus fuse hidden in the unit itself?  Or at least running 12V to it directly to see if it will power on?

I'd get a bluetooth cassette adapter and rock on, if so.

I found a reference to KEH-9020 from Crutchfield ca 1987.  Is it possible the truck came without a radio new?  Might explain the lack of factory wiring?

Agreed to see if you can grab at least some pigtails from another Chrysler product that uses the same wiring.  I did something similar in a project that had the harness cut off.  It took a while to connect every wire up, but now I have wiring close enough to stock that I was able to plug in an aftermarket stereo with an adapter harness and everything worked.

My only concern is if there was an amp in the system, I wonder if the original speaker wires have been bypassed, so you may need to pull the speakers and trace the wires there, too.

In reply to Tyler H :

Instead of a tape adaptor, get a tiny BT ready amp. If I ever get working on my Miata again, that's what I will add to it. 

It seems like he got the connector that mates with that '90's stereo unit.  Just need to put butt splices on the wires for that unit and figure out which wires go from the '90's unit to the '80's vehicle.  Seems like Rob was nice enough to get wiring diagrams together to make that easier.  Power conductors seem easy enough.  It looks like the '80's stereo used a common speaker ground and then the positive side of each speaker used an on-purpose wire.  So there's 5 wires, one for the common ground, and then the front left speaker gets a positive, front right speaker gets a positive, etc.  The "Premium Sound" amp, being premium and all, would have provided an on-purpose negative conductor to each speaker.  

To make that work you could splice the negatives all together on the stereo side of the butt splices and then go through the single butt splice for the vehicle wiring.  A better solution would be running new wire to each speaker as I doubt the factory wiring is all that great for the speakers.  You could still do butt splices if you'd like and run 16ga wire to each location, positive and negative both, and just leave the factory stuff in place.