There are many options to rewire a classic, custom, street or hot rod. With so many options which one to choose can be a daunting task..

What kind of choices are there?

• Universal

• Near OEM (Original Equipment Manufacturer)

• OEM factory correct

What are the differences between the different harnesses?

UNIVERSAL HARNESSES

ALL Universal wiring kits are by thier nature UNIVERSAL..

So technically any universal kit can be used for rewiring any vehicle. Simply put they are designed to fit a street rod or hot rod. Which by thier nature are custom, being custom means the harnesses have to be designed by the manufacturer to fit many different applications. Which is why they will work perfect in any pre-computer era car. Because with the exception of a few switches, everything in every car is about the same just labeled different or color coded different. All motor vehicles share a few things in common, an Engine, Headlights, Turn Signals, Brake Lights, Charging and Ignition systems, Accessories and Gauges. All a fuse block or panel does is provide a fused power source for all those circuits. All you need to rewire any classic are some simple directions, basic tools and an original wiring diagram for your vehicle. You may even find its simpler and definately less expensive to install a universal harnesses than it is to install a OEM harness or try to repair the old one in your car.

In most cases you will need to reuse any model or make specific plugs, connectors and misc items off your old harness. Although the power is provided from the universal harness, you may need to reuse some sub harnesses like the wiper switch to motor harness, Heater - A/C harness, power window and door lock harnesses. Basically any control wiring for accessories, since they are model and make specific.

How can this possibly work on any car?

Simple a switch is a switch, turn signals, headlights, ignition systems, starters, they couldn't care less what switched the power on. All you have to do is run the leads from the wiring harness to the existing switches, steering column, lamps and accessories. All circuits are usually color coded, labeled and numbered as to where they go, so its pretty fool proof. I.E. the left front turn wire goes to the left front turn signal lamp no matter what car it is. You can download the directions for the EZ2Wire series of harnesses at the The EZ2Wire Ebay Store, Once you read the directions you will realize how easy of a project it can be.

Not all Universal Harnesses are created equal.. and there are various types that run the spectrum of costs and quality.

SIMPLE Kits

[ EZ2Wire (E8) ]

These are really basic, you get a fuse box, the fuses, relays, and a little wiring, The wires in these kits are the power wires from the fuse panel to the different switches. They don't include wires for gauges, turn signals, etc.. That said, they are really inexpensive.

ECONOMY Kits 

[ EZ2Wire, EZ Wiring, Its-a-Snap, Gearhead, Painless ]

These are all pretty basic, you get the fuse box, the fuses, relays, wiring, and connectors, that's about it. Directions are possibly downloaded and printed by you and may not come with the kit. These kits are for those looking for the lowest price and are willing to go to the store to get a few connectors and such. Some harnesses like the EZ Wiring (Not to be confused with EZ2Wire), Its-a-Snap and some more expensive Painless models, come with mini-ATC fuses instead of full sized ATO fuses. While this makes the fuse panel more compact, the ATC fuses dont hold up as well in many cases to heavy loads.

MID-RANGE Kits

[ Kwik Wire ]

These kits feature few bells and whistles and are built in the same style as the economy kits, where the whole harness is pre-wired to the fuse block. They tend to feature much sturdier fuse panels, extra thick wire, extra connectors, butt splices, and nice color coded directions included. Examples are like the Kwik Wire kit that includes speaker wire in the harness, and solders all the connections in the fuse panel making it a sturdy kit for off roading, or the EZ2Wire EZ26 (the only 26 circuit on the market) which comes with many extra accessory circuits, like a 40 amp 10 gauge circuit for power lift doors or multimedia applications. Overall they are simple yet extremely beefy kits, and are nearly bullet proof. They tend to be about $150 to $250

SPECIALIZED & NAME BRAND Universal Kits

[ American Autowire (Highway Series), Painless, Centech, Ron Francis ]

These kits usually feature everything you could possibly need in a wiring kit. All the connectors, plugs, ground wires for the lighting circuits, specific detailed directions for each individual circuit, etc..

What all you get with these kits can vary greatly depending on the kit. Sometimes you can get a kit that simply isn't much different than any of the other kits you are just paying for a name, pretty box and pretty directions, and pay much more.

Other times they tend to have more bells and whistles, more connectors, better or more specific directions, etc.. Some kits may even come with some universal switches included (Headlight, Dimmer, Ignition, etc. depending on the kit).

Some like the American Autowire Highway Series, Centech, and Ron Francis harnesses come with customizable fuse panels that include a lot of features to make installation cleaner and more custom.

These tend to cost from $250 up to $600. So you have to be picky when buying these harnesses, in some cases you get what you pay for (i.e. the American Autowire Highway Series, which includes switches, and a customizable fuse panel) and in other cases you don't (I.E. some of the lower end Painless harnesses are no better than standard universal kits, no switches, a generic fuse panel, but still cost over $300 simply due to the brand name).

There are also specialized universal harnesses, like the Kwik Wire 6 volt harness. It is basically a universal harness, wired with a 6 volt flasher and heavier guage wire to handle the amps of the older pre-60s' 6 volt cars. This harness is available only through special order and made specifically for EZ2Wire by Kwik Wire. I commissioned the harness after many requests from owners of Studebakers, Hudsons, and early Ford and Chevy for such a universal 6 volt harness. They tend to cost from $239 for a 8 circuit to $309 for a 22 circuit.

NEAR OEM style Kits

[ American Autowire (Power Plus Series) , Painless ]

With these they are usually the same basic universal kits they sell regularly, but they have a number of extras. Wiring cut to length to fit a specific model, possibly a few plugs for a specific model, and directions that fit specifically to that model, OEM styled fuse panels (I.E. The Power Plus 12 and 18 series from American Autowire include GM OEM fuse panels). They tend to cost from $250-$550. Compared to the cost of an universal harness, I think it comes really clear, that since the wiring tends to be out of sight anyway, a lot of money can be saved by using a a few connectors off your old harness to rewire your next project. Be warned these may or may not have bulkhead connectors included in the kit, most don't (The American Autowire Power Plus series and most Painless Harnesses do not).

OEM Kits

[ M&H, Y-n-Z, American Autowire (Classic Update & Factory Fit series), VAMustang/DallasMustang, Dearborn Classics]

These kits are specifically OEM, some have a factory OEM Fuse Panel (or in the case of the Classic Update harnesses from American Autowire a modern replacement version using modern ATO fuses), include the Bulk Head connectors, and factory correct connectors for your specific make and model. These are by far the best harnesses and easiest to install. They look factory and install like factory. No splicing or borrowing of connectors off the old harnesses, etc.. They are also expensive.. anywhere from $400 for a 1970 Chevelle dash harness to $1800 for a complete factory perfect harness for a 1950 Cadillac Limo from Y-N-Z. Occasionally in some cases rare models may require sending the old harness to the manufacturer so they can salvage some of the connectors that may not be available any other way. If your doing a show car this is truly the only way to go. Only problem is most the harnesses available are for GM makes and models.

Ford harnesses are harder to get and more expensive. Ford made a habit of changing connectors every year and very model, so it makes it hard for any company to reproduce them. In some cases, some of the "OEM" Mustang harnesses on the market (i.e. the Painless Mustang Harness) requires modification of the firewall due to the fact the bulkhead connectors are not available, so they are just like universal harnesses and require reuse of model specific plugs and connectors. So while closer to OEM they are not 100% perfect.

I hope this guide proved to be helpful. If it did I would appreciate it if you would vote "Yes" down below.

Also check out my store as I sell the EZ2Wire, American Autowire, Kwik Wire and can special order M&H harnesses ( OEM GM harnesses from the 1950s' to 1980s' ) and Y-N-Z OEM harnesses ( Specializing in pre-1955 makes and models ).