redoing wiring?

[Dropt72Shortbed]

im in the process of putting a new cab and bed on my truck. the current wiring all works but i want to replace everything for piece of mind and to get rid of all the cut, nasty and added wires etc...

im a bit short on dough and would prefer to finish my air suspension and get the body back on to have it driveable again.

now the question, would it be easier to redo the wiring with the cab off the truck or does it make no difference if its on or off? id really rather do it later when ive got the cash but if its going to be easier to do it now id rather get it out of the way.

also wheres a good place to purchase everything? how many different wiring harnesses are there for a 72 truck?

[Lightspeed]

im also interested.

[BUXMAN66]

go to www.carandtruckshop.com they have some good prices on stuff for our trucks.got a catalog from them and thier prices for some of the stuff i've ordered recently were better than what i had paid at other places.(glove box door emblem,rear-view mirror/arm,decals for engine.......etc.)

[barn9]

Painless is one altenative. Use the search function, this has been discussed in the past. My experience with trying to patch 30 year old wires is that you still have 30 year old wires with a patch, if you get my drift. You'll be much happier with a new, reliable harness than a patched up mess in my opinion.

[hobby67stepside]

If you are willing to be a little bold and not use the original type harness and change some things (such as the connection at the firewall) consider EZ wire. I used their harness in a project and was pleased. I'm now working on a '67 and will use their harness again. You can get like a 21 circuit one for 195. No, I don't work for them or get a commission. I just think its a good product. BTW they may have a specific app for '67 -'72, I haven't inquired about that.

[paintpyro]

Blake,their is a place in Santa Fe springs that manufactures for all the parts places called M and h electrical Fabricators, all factory looking. You are usually buyin all there stuff if you get it elsewhere

[72K10]

I've replaced all the cab and engine wiring in my pickup, and in my opinion having the cab off wouldn't help much at all. Just do a quick look / trace of your wiring, and you'll see that the under-dash wiring will be a little tough regardless, and the engine compartment wiring will probably be easier with the cab on. I would suggest, though, that you go step by step, and as you disconnect one part of your old harness, you hook up that same part of your new. Example: lay out engine compartment harness alongside old, disconnect alternator, reconnect new, move on to regulator, disconnect old, reconnect new. Hope this helps.

[70c10]

Probably won't make much difference with cab off. As far as year goes, make sure you get a AC or non AC depending on your application and also whether or not your truck has a gauge cluster will matter.

[crazy longhorn]

The only wiring you have running to the back/underneath the truck is the tail lite harness.......I would go ahead & set the box & cab on the frame, it wont be any tougher to wire like that & you will have more workspace in the shop! i also agree with the rest of the guys, rather than "patch up" the old harness, you would be way ahead to spend the cash on a new one. Good luck.....crazy AL

[Dropt72Shortbed]

Originally posted by crazy longhorn
i also agree with the rest of the guys, rather than "patch up" the old harness, you would be way ahead to spend the cash on a new one. Good luck.....crazy AL

yea i never had plans to just patch it, i want to replace everything. im building this truck to be a reliable daily driver so i dont want to cut corners. but if the wiring can wait till later then id rather finish the air susp and get the body back on the truck so i can have it drivable again.

[ChevLoRay]

M&H Electrical Fabricators, in Sante Fe Springs, CA., has a web address of www.wiringharness.com.

I have used one of their engine harnesses on my truck, and I have also used a front lighting harness from LMC. I liked dealing with M&H, better than LMC. The folks at M&H know wiring and can talk intelligently with you. People at LMC are just trying to figure out a way to get you to buy from them, i.e., they're customer service/sales people. When you have a problem with wiring, you need to talk to someone who knows wiring. M&H is one of those people you can count on.

As for which to do first, I elect to do wiring before airbags....because the best airbags on the lowest truck don't mean diddly if your wiring is shot and subject to short out. By the time you get thru putting it back together, you will regret not installing a new wiring harness....especially, and I hope you wouldn't have to experience this, if you have an electrical fire due to the old, broken-down insulation on your current wiring.

[Earl Junior]

I just finished this project. I used the kit from Chevy Duty.

I had to reuse some of the factory connectors, but overall I was impressed with the completeness of the kit. It took me about five or six continuous hours to install and it worked on the first try.

Well, mostly.

Was it an option in '68 to get the backup lights to comeon when the brake is applied?

Anyway, I don't think having the cab removed would have been a benefit.

[Dropt72Shortbed]

Originally posted by ChevLoRay

As for which to do first, I elect to do wiring before airbags....because the best airbags on the lowest truck don't mean diddly if your wiring is shot and subject to short out. By the time you get thru putting it back together, you will regret not installing a new wiring harness....especially, and I hope you wouldn't have to experience this, if you have an electrical fire due to the old, broken-down insulation on your current wiring.

thanks for the info.

as for my current wiring, really it all works fine. theres just a bunch of wires that go nowhere and then theres missing wires (gas guage being one) ive also added AC. the current wiring works fine but then again it is 30 years old. i think im gonna get the truck back together and running again then do the the electrical after that.

i have another daily driver so its no biggie leaving the current wiring in there until i get around to it

now does M&H have a specific harness for our trucks? im no expert when it comes to wiring and i figured if i bought the stock harnesses i could just put it together using the stock wiring diagrams. if i purchase one of their harnesses does it come with detailed instructions? ive never dealt with wiring before so i wont know where **** goes, i dont want to be calling them up to ask them where each wire goes, id rather follow instructions and diagrams .

[ChevLoRay]

M&H makes specific harnesses for our trucks, as well as many others. You can tell them what modifications you have made, like 1-wire alternators, HEI ignition system, and they will modify the harness so it looks like factory. All wire sizing and colors are in accordance with the original, so if you are restoring a truck, you can feel good about their harnesses. All connectors, mounting brackets and plugs are spot-on. They're easy to talk to, if you want to give 'em a ring.

[Blue Beard]

The link you posted for Car and Truck Shop.com didn't seem to work.

Could you check this and repost maybe with a phone number as well?

[Palf70Step]

Try this link for the car & truck shop.

http://www.truckandcarshop.com/

[mikej71]

I purchased M&H harnesses for my engine, front lights and dash, and they were all exactly like the originals (except for the splices and melted jackets ). Every connector was in the correct
location, and fit perfectly. I got them from GMC Paul cheaper than M&H sold them, and you can specify HEI, internally regulated alternator, etc.. For me, it was definitely worth not having to deal with a somewhat universal harness.

I'm starting to sound like a commercial.

Oh yeah, I think it would be easiest if the truck was fully assembled.

Mike

['72 Shorty]

I did a painless kit. I really like that the fuse block is all wired up and looks good and every wire has what it goes to along with a number that you can look up in the manual written right on it. That really helps when adding things(like an LED 3rd brake light that is pre wired) on later. It comes with all AC, electric choke, Electric fuel pump and gauge sender to the back of the truck, PW, PDL and some other stuff I know I'm forgetting. I didn't use a lot of the wires. It also had instructions for internal or external as well as High amperage alternators and HEI or points. I also like the 50A maxi fuse between the battery and the entire harness. Best of all, it took all of about 6hrs total to install.

No,I ton't make any money off this either, I was just impressed.

-Jesse

Oh yeah, with the painless, You have to enlarge the hole in th firewall a little(3/8") to fit the new fuse block. that would be easier with the cab(or at least the inner fender) off, but I did it without removing either.

[Blue Beard]

Thanks for the link.

Catalog 1-800-243-8947

Even if you download the catalog, I would advise calling for a hardcopy.

Currently experiencing some problems.