The ol’ ‘48 wiring has seen better days. Truck runs and drives around the yard powered by a 1968 Mustang 302, 12v generator system. Parked in a warehouse in 1970 and updated slowly over years. Mice ate most of the lighting wires up pretty good, so none of them work.

I bought a 12 circuit universal wiring harness to swap, a new alternator, headlight switch, voltage regulator, alt brackets, tail lights, bulbs all around, turn signal stalk, and starter. Took some pics (below) and plan is to remove the old and install the new. I’ve rewired a few old Mustangs, Broncos and a ‘66 F100, so hoping this one goes well. Always a little reluctant to mess with something that is working well. I haven’t looked under the cap, but points will be replaced with a Pertronix ignition module.

If you need any parts for your original harness, let me know. The truck runs and charges now.

 

Rewiring is a good idea. My truck was running fine but I questioned the wiring too…look what I found on the headlights…

 

Gnarly! I often pray for patience, and I need it when it comes to wiring!

 

So ran into the first challenge right out of the gate. The alternator mounts allowed the alt to interfere with the motor mount (maybe why the generator survived the previous owner’s motor swap). The new top bracket will work but the bottom (belt adjustment bracket) will have to be relocated to the inside fender, a mount tab fabricated, and the alternator will hang kinda the opposite of a traditional one.

In other words, I rotated the alternator all the up and will let it swing downward to provide belt tension. I will post a pic when I get it installed. Not getting to crazy with appearance of the brackets as a motor pull and refurbishment is on the horizon and things like spacers and brackets are a lot easier to address on a motor stand. Just making it work for now.

Although it would be cool to get the original gauges working, I foresee an aftermarket oil pressure and engine temperature gauge cluster. There’s already one next to the heater controls but it’s inop and ancient.

 

Interesting engine mounts!

 

Completed the alternator today and started getting the old harness and light fixtures off.

 

I wouldn't run it like this. The engine will vibrate the inner fender well. You need to make that bracket work off of the engine some way. It will crack the inner fender over time. Your engine don't sit still when running

 

Hmm, good point. I will have to take a fresh look at it. My recollection is that to clear the motor mount, the alternator sits so that the adjustment tab is at the 9 o’clock position as you look from the grill toward the cab. The lower bracket would have to be significantly modified for length and the belt would have to be the exact length with no further adjustment ever possible.

The other option would be to figure out how to wire in the old generator to the new wiring harness that is set up for an alternator. I am not adverse to the genny, my first Mustang restoration was a 1964.5 V8 260 3 speed with the same unit. Worked great, I just thought this would be an easy swap/modernization.

Here’s the new harness wiring instructions for an alt, feel free to reply regarding wiring the genny with the new harness:

 

I think It shouldn't be too hard to wire up your generator to work with your new harness. I would make my own voltage regulator to generator harness. Using your old 12 volt generator voltage regulator, you would run 3 wires between the them. One wire for the Armature connections, a wire for the Field connections, and a ground connection from the mounting base of the voltage regulator to the generator case ground. Then run a good sized wire, #12 or even #10 gauge between the battery connection on your generators voltage regulator and run that connection to the starter solenoid on the battery side. And the same sized wire between the Armature terminals of the generator and voltage regulator. That should do it!
edit:
Just follow the 64 1/2 generator diagram you posted and it should work.

 

Fabricated the old genny adjustment bracket, which was already altered by someone. Should be good to go, thanks for the tip….

 

Good work. This will work out so much better.