Topic: 1966 Mustang Wire Harness

[evantugby]

Hello,
I have a 66 Fastback GT K-code, Metuchen built, 23 Oct 1965 kar, no power steering, no a/c, 4-speed with 289 HiPo motor.  I am doing a restoration on it and am looking for the correct wiring harness (s) for the engine bay.  I was hoping someone could point me in the right direction on which mustang parts supplier carries a wiring harness for my particular kar. 

I believe I need the following that National Parts Depot carries but I'm not sure if the K-code had something specific: 
1.  Firewall to Head Light loom  https://www.npdlink.com/store/products/14290_1C-101946-100.html
2.  Engine Gauge feed loom  https://www.npdlink.com/store/products/14289_3B-101929-100.html
3.  Alternator to voltage regulator loom  https://www.npdlink.com/store/products/14305_1G-102014-100.html

Am I missing anything other wires I need to purchase other than main battery + and - wires and Spark plug wires?  Is NPD the best place to get these wires or do concours restorers go elsewhere to buy? 

[carlite65]

regardless of what vendor you may choose you want products from alloy metal. no other maker comes close to their quality.

[J_Speegle]

regardless of what vendor you may choose you want products from alloy metal. no other maker comes close to their quality.

+1 Most of the shops are resellers (though a few make their own parts and are the sole providers of a few parts) so the maker is an important part of the decisions you make when it comes to reproduction parts

[midlife]

1966 is an easy year for harnesses, as there was only one mid-year running change and that affected only the underdash and integration of the emergency switch.  All other harnesses are the same with the exception of the engine gauge feed and alternator harnesses, which only depended upon whether it was an I6 or V8.  Whatever mid-year change for the headlight harness, I've yet to understand what that might be, as they are all electrically identical.  It appears your selection from NPD is appropriate.

You should also look at the main ground cable (battery to block) and block to firewall. 

[Bob Gaines]

Hello,
I have a 66 Fastback GT K-code, Metuchen built, 23 Oct 1965 kar, no power steering, no a/c, 4-speed with 289 HiPo motor.  I am doing a restoration on it and am looking for the correct wiring harness (s) for the engine bay.  I was hoping someone could point me in the right direction on which mustang parts supplier carries a wiring harness for my particular kar. 

I believe I need the following that National Parts Depot carries but I'm not sure if the K-code had something specific: 
1.  Firewall to Head Light loom  https://www.npdlink.com/store/products/14290_1C-101946-100.html
2.  Engine Gauge feed loom  https://www.npdlink.com/store/products/14289_3B-101929-100.html
3.  Alternator to voltage regulator loom  https://www.npdlink.com/store/products/14305_1G-102014-100.html

Am I missing anything other wires I need to purchase other than main battery + and - wires and Spark plug wires?  Is NPD the best place to get these wires or do concours restorers go elsewhere to buy?

If you are concern with what is historically correct then the sparkplug wires are typically radio resistance marked unlike the SX marked wires that the NPD catalog indicates. The 65-67 GT350 were widely photographed back in the day for car magazines. The engine shots in those vintage magazines are extremely helpful in documenting what was typical from the factory. Since the Shelby GT350 was the top showcase for the K code in a production car back then it is logical and reasonable to assume therefore that if it made sense to have been engine performance upgraded from the factory the GT350 was going to have it. Out of the dozens of vintage GT350 engine shots none can be seen with SX wire .Radio resistance wires is the norm in the Shelby pictures. FYI even the all out race GT350 R models ran with radio resistance wires back then . First hand mechanic and vintage photographs confirm.   

[outlawincorporated]

evantugby

Also consider the option of finding NOS 66 V8 wiring looms, I'm yet to have a issue with on any of the cars I have restored.

I have some extras if your thinking of going down that route, drop me a message if you want

regards

PHILL BERESFORD
MELBOURNE.
AUSTRALIA.

[CharlesTurner]

Only thing on the NOS harnesses is sometimes the wire colors can be a different shade or the end connectors slightly different.  The headlight connectors are usually gray on the later headlight harnesses, but not difficult to change out if desired.