Ignition help needed (stumped)

Ok. It still may have the optional 65 amp wiring. So keep that in mind.

Lets look at the '75 wiring diagram. You can then convert it or redraw into layout showing just what you are interested in. That's basically what I did above with the '72.

Here's a section of the '75. As I mentioned above, power distribution is a little changed from earlier cars.
Notice on the alternator's output wire (R6) there is a J1 wire spliced in. 12 is 12 gage
J1 typically designates a feed to the key switch. This arrangement is different from earlier wiring.
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CE2 is the bulkhead multi-connector. There's a seperate drawing or list indicating which cavity.
But we can see the grsay& red fusible link should plug into one of those cavities.

In the diagram you can see the firewall grommet that we've seen cars that have had the rear defrost and 65 amp alternator wiring.
Once your sure the car does not have the 65 amp wiring option, simply ignore or erase those lines. It makes the drawings easier to read.
C13 12 black is the feed wire to rear window defrost. So we can do that right now.
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