I would do further digging. You are doing what, finishing up a new harness? Are you aware of the ammeter wires? Big black and big red under the dash, they go to the ammeter and the black is NOT ground, it continues to the alternator. If you do not have an ammeter they must be bolted together and taped
This a factory harness, or been chopped up/ modified, or what?
On a stocker, losing power to the key and no headlights/ etc means trouble in the ammeter circuit. The path is starter relay, fuse link, through the bulkhead connector (large red) to and through the ammeter, out the ammeter on large black, back out through the bulkhead, and to the alternator
A welded splice in the black ammeter wire runs off and feeds the fuse panel, headlights, and ignition switch.
Stuff about the ammeter circuit, and a simplified diagram from that web page
[URL]http://www.madelectrical.com/electricaltech/amp-gauges.shtml[/URL]
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