Complete wiring harness

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Jackwagon3

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I have a 71 Mach 1 that is going through some major upgrades and I’m wanting to replace the entire wiring harness. I don’t really have many electrical issues but since I have the motor and interior all out, no better time than now to replace all of the wiring.  I’ve been searching everywhere and found Painless and American Autowire has them but they say it comes with “many” of the correct connectors and sockets. Not really fond of the word “many” though. Anyone know of who has one that will have all of the correct connectors and sockets? Cutting and splicing old connectors to new wires seems like I’m defeating the purpose of a new harness.  Thanks for any input.

 

droptop73

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I installed a "Painless" harness in my car last winter. It is certainly not plug and play and requires a bunch of forethought and quite frankly made my brain hurt. I went that direction since I had some fried wires under the dash and wanted to add some aftermarket power accessories in the future. You will be salvaging and splicing many connectors from your old harness. 

If your Harness is in good condition and you plan on keeping the car fairly original have your harness restored by Midlife. 

 

Hemikiller

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Another vote for Midlife, IMO it's better to keep the original wiring intact. 

The only aftermarket harness I have experience with is the American Autowire Classic Update kit. A friend bought one for his 79 Trans Am and it is a really nice setup. He's not a wiring guy and had no issues installing it. They make one for a 71-73. 

https://www.americanautowire.com/shop/1971-1973-ford-mustang-classic-update-kit

 
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Midlife seems to recommend replacing the engine compartment harness so I don’t think they are an option.  I’m having a very tough time finding anywhere that has a 71 harness with sport lamps and tach.  Seems they are all out of stock.

 

midlife

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Midlife seems to recommend replacing the engine compartment harness so I don’t think they are an option.  I’m having a very tough time finding anywhere that has a 71 harness with sport lamps and tach.  Seems they are all out of stock.
That was my original recommendation when I first started out.  For7123's, there's only one headlight harness reproduced, and it is described wrong.  It is for a 71 Mach 1, standard dash. 

I have several in stock, but only a 73 tach headlight harness.  The tach versions seem to go quick out of my inventory. 

I've heard that many reproduction alternator harnesses are out of stock, but a recent customer was able to find one.  Perhaps the supply shortage is beginning to abate.

 

BFH 429

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I have a 71 Mach 1 that is going through some major upgrades and I’m wanting to replace the entire wiring harness. I don’t really have many electrical issues but since I have the motor and interior all out, no better time than now to replace all of the wiring. I’ve been searching everywhere and found Painless and American Autowire has them but they say it comes with “many” of the correct connectors and sockets. Not really fond of the word “many” though. Anyone know of who has one that will have all of the correct connectors and sockets? Cutting and splicing old connectors to new wires seems like I’m defeating the purpose of a new harness. Thanks for any input.
Jackwagon3, I'm in the same boat. Just getting to the harness portion of the build. My old harness seems shot. Appears brittle and had a lot of hack job adds over the years. So, I'm thinking of doing a painless universal replacement as a starting point. I originally had heartburn about going this route, because this universal harness set does not have the original Ford mating connectors included (to interface with tailamps, heaterbox, etc). However, I questioned them a bit more and asked them where they got their connectors for a 70 drop in harness (because they make direct replacements of those) and they indicated Del City, Allied Electronics or Mouser Electronics. So, I believe these companies should carry some or all of the original Ford style connectors that you could graft on. The painless universal harness is color coded to original Ford standards, so, should line up with a schematic. What did you end up doing?
 
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When it comes to the various connectors on the wiring harnesses, even though you have a 71 Mustang, I suggest you get a wiring schematic from Forel Publications for 1973. The reason is their schematic is colorized, and shows much more detail than the 71 schematics i have seen, especially when it comes. The added detail includes identifying the grounds and where they are located, as well as showing all splice locations. The 72 and 73 schematics also have drawings the various connector shapes and where the various color coded wires plug into said connectors. Although both 72 and 73 schematics are both an improvement over 71 and prior schematics, I find I use the 73 schematic most often. There are some fairly minor differences between 71 Mustangs' wiring and the 72 & 73 models, but nothing significant. If you do not yet have the Forel Publications manuals for 72 or 73 you can find them at:

https://www.forelpublishing.com/clickbank/index.html
 
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