Any Electricians in the Audience??

[BadBird]

Would one of you electrical geniuses look at how I have wired my rear lights and see if it looks OK. I know a little about some issues but electrical is above my brain capacity. I am using a E-Z Wiring harness. E-Z for some, not me.
Attached are two scans. One is a pic of the book schematic and the other is a sketch of how I am wiring it. You will have to enlarge the pics to see what I am doing. There are four wires in the harness going to the back lights. The Tail light wire splits off to both tail lights and also splits off to the license light. The Backup wire also splits off to both tail lights. There are of course seperate wires to the Left and Right turn/stop lights.
I added some notes to my sketch to try and explain the ground wires?? It looks like if I add a ground wire between the tabs that stick out from the tail light back and go to a a common ground and then also add another ground wire between the negative wires that come from the back up light plugs to a common ground that it should work?
There isn't a ground wire coming from the license plate wire so I am assuming it is a structural ground at the light housing?
Thanks a bunch for the help. Larry

[Luva65wagon]

Looks pretty good to me. Nothing jumped out at me anyway. You can join the grounds at the tail-light ground tab and the back-up and run it to the other side, do the same and do one ground for both. I believe the ground screw was near the center support where the license light positive came up. It's really better to have all the wires connected together and grounded at one place. It's far easier to trace faults if you're not checking ground differentials at various points.

Yes, some lights, like the tail light buckets, also had a ground wire since there's a big rubber gasket and some potential for the ground to not be very good without one. If I recall correctly, my license plate light bolted to the bumper, which was ground.

In the early 60's they used all switches to switch the hot wire for like door light switches and the lights themselves were grounded. By the mid 70's they'd switched to the way GM and many others did - they switched the ground circuit. So the wiring to the light was always hot, and they ran another wire from the light to the switch and when the switch closed the switch went to ground. Never quite "got" that, since this meant instead of one wire running to a light, they had to run two. Sadly a lot of these aftermarket wiring kits used the negative switching fundamentals, which made it hard to do a lot of the Ford stuff without jumping through a few hoops to use them.

My friend has a 65 Mustang (the wiring in it is almost 100% the same as yours) and he wanted me to use a kit called "It's a Snap" and after I studied their wiring diagram (what crap that was) I finally talked him into letting me repair and reuse all his existing wiring and upgrade it as needed to accommodate the improvements he wanted to do. So glad I did. We sold that kit at the swap meet today. Glad to see it go.