Which wiring harness

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Jacob Miller

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Howdy all,
I have a 73’ C20 Cheyenne camper special that I’ve been working on and loving for the last year, my next project is a complete re-wire of the truck as the existing electrical has been spliced to death. I’m looking between the painless kit and the American auto wire. Can anyone recommend one over the other?

The truck is currently stock but in the near future will be getting an edelbrock 4flow setup, in-tank pump and eventually dual tanks with separate pumps, vintage air heat & ac, electric fans and possibly more as funds allow. The question is which harness is best and why?
 

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Doppleganger

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I like the Painless alot. The turn key kit is about $700. I saved my firewall gang plug and bought a 28 circuit universal with a GM column for about $300. Then got all new connectors for the firewall plug to hook into it.

I've got the PF4 also so between that, electric fans, AC, PW, etc.....wanted the extra circuits.

I posted the PNs for the kit I have before - just have to find it.
 

AKguy

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I have had great success with American Autowire. Did a complete update kit for my daughter’s Chevelle, and all but the dash harness on my K30.
 

Jacob Miller

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It’s probably worth mentioning that I don’t need an OEM style gauge harness as I’m using a Dakota digital dash already (and loving it)
 

ak4life

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Howdy all,
I have a 73’ C20 Cheyenne camper special that I’ve been working on and loving for the last year, my next project is a complete re-wire of the truck as the existing electrical has been spliced to death. I’m looking between the painless kit and the American auto wire. Can anyone recommend one over the other?

The truck is currently stock but in the near future will be getting an edelbrock 4flow setup, in-tank pump and eventually dual tanks with separate pumps, vintage air heat & ac, electric fans and possibly more as funds allow. The question is which harness is best and why?
Dont go americant autowire, i spent nearly $900 for the "73-87 classic update kit" and am fully disgusted for many reasons.....for one) finding out later that i could probably get the same or better for half the price. Second) thy skimped on the lamp sockets, instead of using the newer style for 3157 bulbs its the old twistlock style (cheapskates) also didnt include the bulbs for lamp sockets
(really are cheapskates) . Third) the wire wads up on you and can kink if not careful, and they are super long, i spent more time constantly untangling the wire then i did wiring, its the type of coating that would make wires stick together. Real pain in the ass! Fourth) is there is nothing plug and play about this harness, you are making every cut, every crimp, every snap decision that isnt noted on instructions, imo this should have been a more "out of the box" kit, it was "SPECIFIC" for my vehicle why am i having to crimp all connections and ad the plugs. Fifth) the instructions arent even specific to that range of truck, almost every squarebody from 73 -87 had dual tanks, this has instruction and one wire for a newer style or blazer setup where one tank is in rear of vehicle.. that makes absolutely no sense. Im just so pissed at the amount of money i spent before doing better research. I would recommend a $150 kit off the internet before waisting your money on american autowire !!
 

AuroraGirl

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Dont go americant autowire, i spent nearly $900 for the "73-87 classic update kit" and am fully disgusted for many reasons.....for one) finding out later that i could probably get the same or better for half the price. Second) thy skimped on the lamp sockets, instead of using the newer style for 3157 bulbs its the old twistlock style (cheapskates) also didnt include the bulbs for lamp sockets
(really are cheapskates) . Third) the wire wads up on you and can kink if not careful, and they are super long, i spent more time constantly untangling the wire then i did wiring, its the type of coating that would make wires stick together. Real pain in the ass! Fourth) is there is nothing plug and play about this harness, you are making every cut, every crimp, every snap decision that isnt noted on instructions, imo this should have been a more "out of the box" kit, it was "SPECIFIC" for my vehicle why am i having to crimp all connections and ad the plugs. Fifth) the instructions arent even specific to that range of truck, almost every squarebody from 73 -87 had dual tanks, this has instruction and one wire for a newer style or blazer setup where one tank is in rear of vehicle.. that makes absolutely no sense. Im just so pissed at the amount of money i spent before doing better research. I would recommend a $150 kit off the internet before waisting your money on american autowire !!
I agree its very strange they didnt update the bulb sockets.. however, wouldnt this require them to also give you new plastic lenses? I believe the twist base has a different plastic retainer design between the old style and newer vehicles, if not maybe a diameter difference?

I have a lot of 3157 sockets I could compare. But GM was pretty consistent on using the bulb number and a matched holder across many applications, not necessarily 100% without change but at least often
 

SquareRoot

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What's your skill level with electrical circuits? I have everything on my 85 that you mentioned. It's going to be a HUGE job, I promise you that. If you have the time and can put the truck out of service for a few months, I highly suggest doing everything at once. Going back and hacking into the work you did previously to add/update this/that is a tremendous waste of time/money/energy.

Decide on EVERYTHING you want to add/modify before you even start. Gut the entire electrical system, install every item and route the harness and all its sub-circuits before you start making actual connections. If you want a clean, safe and orderly end result it requires a LOT of effort. With that said, I used a universal 18 circuit harness (GM connectors) on a previous vehicle and it was great. I opted for a Summit Racing Branded kit that had everything the "Name Brand" kits have at about 1/3 cost.

Invest in some quality tools up front. I bought a WeatherPack terminal kit and crimpers and converted all the factory 56 style OEM plugs to WP for long life and piece of mind. I have no regrets.
 

Raider L

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@AKguy,

So what was your experience with American Autowire? Compare what @ak4life said and were your experiences about the same, different, better, what?
 

Curt

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I used a American Auto Wire kit several years ago on a 1980 k-10.It was a decent kit,however it was a generic GM kit that fit a wide variety of models.There was definitely some areas that I had to make up my own set up,like the headlight harness,windshield wipers.

It wasn’t advertised as a direct replacement for my truck,but it did allow me to redo all the wiring.

Painless is direct.I have no doubt you may have to be just a little creative in some areas even still.

I would definitely go painless.
 

AKguy

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My experience with the entire upgrade kit was in my daughter’s 1969 SS396 Chevelle. Every piece of wiring came out. The instructions/drawings were very good, lots of extra wire, and when I finished everything worked. There was a lot of soldering/crimping and having the correct crimping tool(s) is a huge help. Also, as you progress through the “phases”, you may be left scratching your head about a wire or two, but it all becomes clear as you move on. I have used the complete front, rear, and trailer harnesses on my square, no problems, were plug and play.
 

AKguy

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You might see if anyone has used the M&H harnesses. One of the harnesses I ordered from American Autowire, the rear I believe, had an M&H tag on it, so they use their stuff occasionally.
 

Jacob Miller

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Just wanted to update this thread, I went with the painless harness. I can’t say enough good things about it.
 

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ali_c20

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I also have the painless wiring sitting on the shelf for my c20 project. I used painless for my wife's 69 Mustang sportsroof and really like it.
 

AuroraGirl

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Just wanted to update this thread, I went with the painless harness. I can’t say enough good things about it.
Also is that a cast bracket for the ps pump(as opposed to the multipiece ones originally came on these)
 

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