Mustang American Autowire Complete Wiring Harness Classic Update Kit 1965-1966
Part Number: 510125
American Autowire Classic Update Kit Complete Wiring Harness for 1965-1966 Mustangs.
The Classic Update Series is a complete wiring system in a box, giving you everything you need to modernize your classic Mustang's wiring system. Allows for most aftermarket accessories such as: gauge packages, heat and air conditioning systems, power windows, etc.
American Autowire's Classic Update Kit's instrument cluster wiring is designed with a separate “cluster harness disconnect” system for easy service and assembly. The best aspect of the disconnect system is that any gauge cluster package can be easily and neatly wired in. This includes JME ENTERPRISES, AUTOMETER, CLASSIC INSTRUMENTS, DAKOTA DIGITAL, STEWART WARNER, and VDO just to name a few.
- Correct replacement headlight switch with internal circuit breaker
- Original Ford styled headlight switch connector
- Headlight enhancement relays allow for high-powered halogen headlights
- Separate relay controlled circuit for cars that have stock or aftermarket fog or driving lamps
- Complete wiring for all running lights, brake lights, directional lights, license lights and third brake lights
- Correct replacement ignition switch for use with original bezel and tumbler
- Correct original ignition switch connector
- Standard turn signal flasher and hazard flasher mounted on fuse panel; horn relay mounted on harness
- New ATO Fuse box fits the in center of the firewall away from header and A/C ducts and allows for easy fuse and circuit breaker accessibility
- All required hardware supplied
- Original switch connector bodies! (Exclusive to American Autowire)
- Separate optional under-dash light sockets along with original dome/interior light wiring
- New floor dimmer switch is provided and mounts in the stock location
- Steering column connectors will plug directly into most aftermarket steering columns. Directions and an adapter with terminals are included for running a stock Mustang steering column.
- Color schematics and easy to understand instructions included
Front lighting includes: extra long leads for special routing when custom under hood appearance is desired. All headlight, park light, fog light, and directional light leads are provided, as well as a switched trigger wire for electric fan relay (usually recommended with AC).
Engine wiring includes: feeds for coil, tach, water temperature, oil pressure, brake warning (with later updated extension if necessary), and electronic speedometer (if necessary). A heavy gauge alternator feed wire is provided for a typical 1 wire high-powered installation. This kit is NOT compatible with original style alternators or points distributors. It’s wired for electronic ignition such as the Pertronix Ignitor.
Rear body wiring includes: backup light lead and ground wires, stop and tail light lead wires with proper focal length sockets, third brake light wire and the correct license plate lead connection for use with your stock tag lamp. Fuel tank sender wire and sending unit extension are also included.
Rear body harness assembly plugs into the main harness behind the left hand kick panel for easy accessibility and allows for original or custom routing.
*This 1965-1966 wiring harness cannot be used with factory (or original-style aftermarket) A/C systems, which interfere with the fuse block placement.
*American Autowire recommends this kit for MODIFIED original vehicles, not OEM restoration projects.
*Does NOT support ammeters.
When we ask our customers what the most intimidating part of working on their classic Mustang is, the answer we usually get is wiring. Original wiring is often frayed and brittle, plus you never know how many times in the past it’s been cut or messed with. All it takes is one bad wire or one bad ground to take your Mustang off the road. If you’re looking for originality, we carry a complete selection of replacement harnesses, but if you’re looking for a modern harness flexible enough to be used with your custom build, check out the harnesses from American Autowire.
This kit is part of their classic update series for the ’64 through ’70 Mustangs. It allows you to replace your harness, while also upgrading to modern accessories. Let’s take a closer look at what’s included in the kit. The first thing you see when you open this box is going to be this stop page. This page isn’t designed to intimidate you from the installation, it’s more to tell you what the harness can and cannot do. The harness is designed to work with a modified car and so will not work with some stock components.
For example, it does require a one-wire alternator. All of the wiring for the one wire alternator is included. This will bypass your factory ammeter gauge, which is a safety concern when running a higher output alternator. You also have to have your tach modified to work with a negative feed. The original positive feed tachs will not work with aftermarket ignition systems and can also cause problems.
Instead of your typical installation manual, American Autowire provides eight pages of high quality color diagrams, as well as mounting templates for your kit. Once you open the box and all the bags up this is what you have in the kit. It can look a little intimidating at first. American Autowire does everything they can to make it that you can do it yourself. All your wires are labeled so not only do you have the color diagrams, each individual wire has a label on it stating where it goes.
Your fuse box is also completely labeled, as well as a bank of relays to keep all the relays in the same location and original style connectors whenever possible. The rear body harness is removable making that easier to install as well. The kit includes a new headlight switch, as well as a new dimmer switch. This kit here is specific to the ’70. It allows you to relocate the wires since the ’70 has the ignition in the column as opposed to on the dashboard.
This kit here is for your gauges. It allows you to wire up aftermarket or factory gauges, as well as make them removable. They also include all the relays and fuses, grommets, terminals, as well as a practice kit to make sure you’re doing the terminals right before you put the harness in the car.
Taking a closer look at the fuse box you’re going to see your flasher, your battery, your normal fuses. There’s also additional fuses for fog lights, power windows, gauges, AC and heat, as well as accessories. That makes this very flexible for adding modifications to your car.
Installing a harness like this may not be for everyone. If you take your time and follow the instructions, this classic update harness from American Autowire is an excellent choice for your resto mod.
Issues with your wiring? Get this kit!! (1966 Coupe)
On 3/27/2012 1:09:52 PM,
slvrblu66 from WA
I had a dead short somewhere in my original wiring. I really wanted to stay original but this kit had relayed headlights, fan relays and all the power options you could ever want built right in. So I went for it. The price was better than a painless kit and install was a easy. Took about 5 days to install for me but I wrapped all my wiring. Be sure to get the crimpers, yes they are expensive, but if you have a classic car spending money is part of it and you'll end up with a perfect install. I installed silverstar headlights and LED lights front and rear. By far the best thing I have done so far. Be warned though you will have to convert to a 1 wire alternator.
Car is like new again!
On 2/20/2012 11:19:17 PM,
Josh C. from
What a great wiring kit! Simple concept and pretty straight forward on the install, but time consuming if you have one person and only weekends to tackle it. Took me one month to tear out the old and install the new....9-10 hours per weekend. Tech support was great. The only complaint I have is the instructions label their connectors with letters, i.e. "Connector B", but they do not have a reference sheet for these connectors. Their crimping tools are a must to do the job right. Everything worked on the first try!! Thanks AAW!
1966 Mustang Coupe Install
On 11/12/2011 10:12:32 AM,
Rudy Taverne from ID
This is one awesome and easy wiring harness to install. Worked perfectly! Just need to invest in the proper crimping tool from AAW to do the job right the first time. Tech support was there and available to answer any questions I had. Thanks American Autowire for a great product!
Complete, but not complete too
On 5/15/2012 12:15:36 PM,
Ken N from WA
I like the harness, well labeled and fairly straight forward. It is considered and update kit not a true complete wiring harness. There are lots of wires that are not needed, unless you have your ride tricked out with electric windows & door locks. It, also, does not have wiring for running the stock alternator w/external regulator, or the windshield wiper switch. It is set up to run every conceivable interior courtesy light but not to run a three switch blower motor for the heater. Also, the steering column needs to be re-configured to a GM style plug to hook up the turn signal & horn. I should have expected that since AAW has more GM products than Ford. There are lots of stuff they don't tell you and you figure out once it's too late.
Mustang American Autowire Complete Wiring Harness Classic Update Kit 1965-1966