Can somebody please provide for me a nice, clear, close up picture of the engine wiring harness where it attaches to the firewall? I thought I took some pics, but cannot find them, and I am kind of at a loss as to how the short 10 gauge red wire with the "Y" or "fork" connector attaches to the firewall harness. I believe this provides power to the inside of the car, so any help is certainly appreciated. Also, if memory serves, I need to run a 10-12 gauge wire from the positive battery cable and mount this to the fender inside the engine compartment? Yes, I'm this close to firing up the 455 I transplanted...... Thanks!
Not sure what you are referring to as far as the short 10 gauge red wire. If you run a wire from the + battery cable to the fender, that will be a direct short. Maybe these pages from the 66 Chassis manual will help. The engine and lighting harnesses plug into the firewall one way. Unless the harness is butchered, there should be no reason to modify anything.
Here's a crappy pic from 14 years ago that may show what you need. If you want a better pic, it'll have to wait until the foot of snow we're getting tomorrow melts. Note the junction block/horn relay.... that's the distribution point for the battery power on the 65-66 GS. It would be a good idea to put a fusible link between the junction and the supply at the firewall block. Buick did that in 1967, but the junction was often at the starter on other engines. There was a 66 Buick service manual online at Team Buick if you need a wiring diagram.
The heavy red wire at the fuse block is spliced into the heavy red wire between the alternator and junction block. That's why it looks like it's not coming from the junction block. After the firewall, it goes to the fuse block, ignition switch, and headlight switch. A short to ground in that path means your battery is shorted to ground and stuff is going to get HOT. Hence the fusible link recommendation!
Appreciate the replies, but I've attached a photo to better illustrate what I am trying to ask. The red arrow points to the red wire in question, and the yellow arrow points to where it seems that the wiring diagram instructs this to go. I do have a chassis manual with all of the diagrams, but they are too small to really pinpoint. You can see in my pic that for now I just have the engine harness plugged in to the bulkhead, I will be adding the harness for the lights and other stuff once I get the car fired up and going. I have been told by M&H Electric (which is where I bought the harness from) that it instructs this wire to plug into the bulkhead to provide power to the interior, I just do not see a place for this. Again, any help is appreciated.
The red wire that you are referring to is attached to the flat copper post above and between the two plug sockets with a machine screw and star washer. It is responsible for bringing power from the starter positive cable to the dash harness.
Makes sense, thanks much! This is what happens when you tear stuff down and don't get back to it for years....
