1970 300 dash harness

Fireguyfire

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I’ve recently bought a 1970 300 convertible that had a few electrical issues.
The previous owner had (poorly) installed a B body painless wiring harness in the car, and it was a poor decision.
Luckily he kept the factory harnesses and I’ve gone through the main dash harness and have cleaned and tested every wire.
I’m about to reinstall the dash harness and am looking at the 2 sided fuse box. I might be missing something but I can’t seem to figure out how the fuse box is supposed to mount through the rectangular hole in the firewall.
It would be great if someone could post up a photo of how the factory fuse panel box is supposed to mount through/on the firewall.

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I typically deal with 68's so I could be wrong, but the fuse block doesn't mount in the firewall. I mounts to the underside of the dash. There is a bulkhead connector that goes in the rectangular hole.

Here's an image from another thread.

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This one is definitely a 2 part fuse block, with one side (white) housing the fuses and the other side (black) housing the engine bay connectors.
I’m assuming like B and E bodies that it sandwiches on either side of the firewall?
The issue is that there are long “posts” on the 2 bolt points on the back of the white parts, and metal spring clips on the mating black side. My issue is that it appears that there would need to be fairly large holes in the firewall for these 2 opposite side posts to go through so that the metal spring clips can lock the 2 pieces of the fuse box together.
I don’t have large holes in those locations; just have small holes I’m assuming for the long bolts to go through that then fix both sides of the fuse box together on each side of the firewall.
A good photo of each side of one of these correctly mounted would be very helpful.
 
I'll go out after lunch and see if I can get a pic or two.
 
This may help. It's a pic I found on the net. It shows the fuse block and the bulkhead connector it clips too. This one happens to be a '70 E Body. I'm headed out and see if I can snap a pic of mine.

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A quick pic of mine. The new hardware they installed in my neck a couple weeks ago won't let me crawl under the dash right now or I'd get some better pics.

Good pic of the part number though.

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Note the burnt tail light fuse cavity. A remnant of a previous owner's doings. All is good now, but the scars remain.
 
Thanks Big John, I appreciate the photo and hope your neck gets better.
Next time you are under the hood could you take a photo of the engine bay side of where the harness comes through for me?
 
Thanks Big John, I appreciate the photo and hope your neck gets better.
Next time you are under the hood could you take a photo of the engine bay side of where the harness comes through for me?
I'll grab one tomorrow.
 
Looks like we have the same part number which is a good sign that it is the original harness.
 
Hopefully this photo shows what I was trying to explain; you can see the metal spring clips from the black half of the fuse box that snap into the white half to hold them together, and then they get screwed together.
The only way for these spring clamps to work would be large holes in the firewall outside of the rectangular opening so that the spring clips can go through the firewall to click them together.
This is the main thing that has me stumped.

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Here’s the part number on the fuse panel which matches Big John’s which is interesting.

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Hopefully this photo shows what I was trying to explain; you can see the metal spring clips from the black half of the fuse box that snap into the white half to hold them together, and then they get screwed together.
The only way for these spring clamps to work would be large holes in the firewall outside of the rectangular opening so that the spring clips can go through the firewall to click them together.
This is the main thing that has me stumped.

View attachment 482317
That half that fastens to the firewall is inserted from the inside, not from the engine side.
 
Ah, so both halves are attached together, and both then go on the inside of the firewall with the black side sticking through from the inside, correct?
 
My fenders are still off so this is an easy shot to show the firewall side of the fuse block.
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Here is a pic of my ‘73 without the engine bay harness attached.

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You can clearly see the screw ends that fasten the box from the inside. Hope that helps.
 
This is the kind of thread that makes me so happy this site exists. My 68 would have probably burned to the ground years ago if it weren’t for the sages of c bodies.
 
I agree; I will have more wiring questions coming as the original harness has been monkeyed with a bit, and I’m looking for any tips on gauge cluster and switch cleaning, etc while I have the entire dash out of the car.
I’m restored several B and E bodies, but this is the first C body I’ve owned.
 
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