I plan to put a new wiring harness in my 55 Panel. What's the best technique? Can I remove all the wiring in the whole truck and then install the new harness or should I leave the old and replace as I add the new? Maybe the question is this -- will I regret tearing out any of the old wires? It would make cleaning up easier with the old wires gone but I don't want to find too latre that I should have left something in. Make sense?

Akso, any great ideas on mounting the fuse block to have better access than up under the dash? Glove box maybe? Any thoughts appreciated.

Jeff in northern Wisconsin

 

Depends on your abilities. If you are competent at wiring, pull it all and take some pictures. If not, you can still pull all the old stuff leaving small pig tails of the current wiring on all of the components. Take detailed pictures and note what color went to each device. If your not worried about stock, put the fuse block any place you want it.

 

After market harnesses are pretty straight forward. They come with detailed hookups for most components and plenty of wire. If you are not going to use an after market setup and you want to replace it all wire by wire then make note of everything in writting and pictures.

You can put the fuse block anywhere you like so long as it's DRY!!! Your worst nightmare will be getting that block wet, other than that put it where you like.

I used a set of DC marine breakers instead of fuses because "...." happens and fuses are hard to find in the middle of no where and foil around a fuse is asking for trouble! I wired my whole truck one wire at a time. It took me about 7 hours.

Look for a wiring diagram for the year truck you are working with and if you are using any new electronics like Electronic Fuel Injection and Electronic Ignition then get a wiring diagram for the year of those components. Most of those new item do NOT like being hooked up wrong.

Make sure you use AUTOMOTIVE wire as well as the right Gauge for the wire as a single melted wire in a harness will destroy most of the wires around it. Not to mention trying to breathe that smoke and see where you going in the middle of traffic is NOT fun...

One last thing... make sure your grounds are good and tight. Battery to frame and battery to cab. Most wiring problems can be traced back to a bad ground.

Scott

 

And engine to chassis. This one is the most often overlooked.
The primary reasons for rewiring is to change from 6V + grnd to 12V - grnd, to be able to add more circuits for modern electronics and accessories, to fix and/or organize the rats nest most 50 yr old truck wiring has become.

The premade harness from places like EZ Wire or It's a Snap is the most economical and easiest solution IMO. Unless you already have some accessories you plan on reusing, I'd just rip it all out and start over. No good reason to work around a mess and it could make for extra confusion. Leave any wires for aftermarket stuff until the end. Plan how you will route the wires from the fuseblock out to the various places they need to go. Try to keep it neat and organized, and leave some slack
I mounted my fuseblock to the side of the suspended pedal brace to the dashboard using the snap in mounting setup on the block so I could do all the wiring then snap the fuseblock to the mount. Another idea might be to mount the block to one leaf of a standard door hinge and bolt the other leaf to the bottom edge of the dash so the block could swing down and hang from the bottom of the dash for access. When you wanted to hide it just swing it up behind the dash and secure it there with a spring clip or even just a zip tie.
You could also mount it to the kick panel, or under/behind the seat. I'm not fond of in the glove box since people throw a lot of small loose items in there that move around. A stray coin or hairpin shorting out the terminals could be "terminal" for your truck.

 

I put my fuse block inside the cab behind the kick panel on the driver's side mounted to a piece of aluminum that is attached to the back side of the door post or jam. I am using a wiring kit from Haywire, so far so good.I left the old wiring in tact as much as possible until I was sure I didn't need it any longer for references. It depends on the engine wiring/electronics that you have.Good Luck, JNB