Question for the electric guru's

[Money_pit]

This may be a dumb question but this is my first resto.
I have a good harness from a donor truck, same year and everything as the truck that I'm trying to get together (in my sig). It has no cuts or splices; nor any wires tapped in or anything..... Perfect shape. So, is it a bad idea to use it inside the truck? And then I was also wondering if someone has made a harness that would plug into the firewall and let me use a cs style alternator, hei, and electric fans?

[Lurayfarmer]

I'd say go ahead and use the full harness if it is really clean and solid. As to wiring in extras, you won't find a made-up harness for that. I would add the wiring you need as you install the main harness so you can run the wires inside the same conduit. I do recommend enclosing big bundles of wires in plastic loom. Just a little extra insurance against shorts and it's invisible under the dash.

[Money_pit]

Kinda what I figured. I was really looking forward to that harness
Looks like I'll get to modifying thanks for the input Bill .

[mechanicalman]

Originally Posted by Money_pit

This may be a dumb question but this is my first resto.
I have a good harness from a donor truck, same year and everything as the truck that I'm trying to get together (in my sig). It has no cuts or splices; nor any wires tapped in or anything..... Perfect shape. So, is it a bad idea to use it inside the truck? And then I was also wondering if someone has made a harness that would plug into the firewall and let me use a cs style alternator, hei, and electric fans?

X2 on using the original, un-cut and un-damaged harness and easy to make the mods you propose. I'd buy this for the alternator mod, it's plug and play and you don't have to hack your harness in that area:
http://www.americanautowire.com/shop...rsion-kit-4567

I would however, modify the harness before I installed it on the power wire going to the coil. I'd completely replace that coil resister power wire with 14-12 gauge automotive quality for the HEI and use one of these connectors, depending on if you have a tach. If you want to go 12 gauge, you will need to remove the spade from that connector and obtain a new one to crimp to your wire, otherwise just splice a 14 gauge wire.
http://www.summitracing.com/search?S...HEI%20pigtails

For key-on power to trigger the cooling fan relay/s, I'd use the ign un-fused spade on the fuse block. You might consider wiring that one from the back as well (if possible, not sure) as long as the fuse block is out. If you use multiple relays, this instruction shows how to avoid feedback in the wiring (it's only for single fan but good info on the relay installation to avoid the need for diodes).
https://www.youtube.com/watch?v=-bqIdUVBsMU

For the cooling fan motors, install a heavy duty junction block and splice the positive battery cable to it or simply buy the right cables to make the installation. Then use appropriate sized wires going from that to power the cooling fans motors. You might consider a fuseable link, inline fuse, or circuit breaker on that. Without specifics on what you want, that's all I have right now.
Do you want a low/high speed option on one of the fans?
Do you have a/c?
Personal specifics.

Dual fans with shroud.
http://www.ebay.com/itm/Dual-11-Elec...ebb978&vxp=mtr

If you can afford it, they make some nice radiator/dual fan combo units.
http://www.ebay.com/itm/Radiator-wit...e6fb02&vxp=mtr

[mechanicalman]

Some connectors without the wires if you want to run a heavier wire on the HEI:
http://www.americanautowire.com/shop...i-ignition-con

One for the tach if you have one, no need for a heavier wire.
http://www.americanautowire.com/shop...i-tachometer-l

[Money_pit]

Mechanicalman you sir are brilliant many thanks
My current set up the po actually ran a 12ga wire directly from a keyed spot on fuse panel truck had hei when purchased. I'm thinking of doing the billet dash with the autometer gauges. Would you suggest electric gauges or mechanical ? I Do not have any experience with electric ones always ran the mechanicals. And good link on the fan power.. That aluminium radiator /fan combo looks awesome and you can't beat that price. Thanks again

[mechanicalman]

I've never ran anything more than stock gauges. I'm contemplating attempting a volt meter install to remove the amp meter.

I'm thinking the electric gauges are as good as the sender matches the gauge, but IMO that's no worse than a gauge's ability to measure oil pressure. I think after that the only other mechanical gauge is the speedo? Why not.

[gmachinz]

How much room do you have for an electric fan? Measure the distance between the radiator fin area and the water pump shaft. I think you may have room for a single, shrouded 18" Motorcraft fan which are 6" in depth. Far more robust than any of the aftermarket Spal or Felx a lite fans, these fans are multi-speed capable and move 4500-4800 CFM @ an amp draw of 26A on full speed. When used with my resistor harness, there is no inrush spike current to worry about.

Even better is the fact you want to upgrade to a CS alternator-why not go with a GM serpentine style bracket swap? I have harnesses for 105A or 140A CS alternator conversions as well as complete serpentine bracket conversions for both amp outputs and modified under hood engine harnesses to complete the setup. PM me if you'd like some ideas-I'm gradually adding 67-72 updated under hood harness options using late model accessories so let me known if I can help you out!