Where does this wire go?

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RaysnCayne

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Hey guys,
Sorry for this one, but I couldn't readily find the answer after some searching in the forums.
Does this wire (the big red one I'm holding in the first pic) go back to this junction block on the firewall?

Backstory:
I bought an '86 C10 with an unknown SBC in it. The engine harness had been hacked out of it. (I think it was originally a 4.3 and someone was in the middle of doing a V8 swap). I bought a factory V8 harness from a junkyard sbc out of an '84 C10.
I've managed to route most of the "new" harness where it needs to go. But IDK if this bigger red wire (which seemed to go right past the junction block as originally plumbed in the factory harness) needs to go to this block, or somewhere else?

Follow up question:
Can it be as easy as screwing the 1984 V8 harness into the original 1986 fuse block and the V8 will work like factory?
Or are there some minor changes between those years that would necessitate me either having to find a 1986 V8 harness or swapping the fuse block over to a 1984?
 

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Ken B

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that appears to be a heavy gauge wire, does it go to the starter from that junction block on the firewall?
 

Rome03

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It either goes to the starter or the alternator
 

RaysnCayne

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The eyelet doesn't fit any of the starter lugs.
And I already have the alternator wired up from this harness.
Should there be two wires on that lug at the back of the alt??
(Although there's an extra wire that I'm holding that was tapped in at some point.)
 

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Smtty58

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I'm guessing that may have been for an electric choke.
 

RaysnCayne

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The one I currently have on the alt lug? Or this big red one?
(I would think electric choke wire(s) would be pretty thin.)
 

RaysnCayne

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Here's how the harness looks on the starter. All seems good to me, Y/N?
 

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RaysnCayne

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And here's how the wires look near the alternator. The wire that naturally falls to the back alt lug looks like it's had its eyelet replaced at some point. But it does look like it should be the one going to the alt lug vs. the nice OE-looking red one that looks like it has to double back to get to the alternator. The nice red one does sorta fall beside where a choke apparatus might be on a carb.
 

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straydog371

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Here's a picture of my alternator wiring if it helps.
FYI there was a fairly recent thread from a member that accidentally melted the fusible link when one of the alternator lugs grounded out when he was adjusting belt tension. Rubber boot or some type of insulation recommended.

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Smtty58

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Elec choke is a small 14-18 Ga blue wire.

Yes, but that wire was tapped in by a previous owner, using whatever he had.
 

legopnuematic

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If the other end of this wire goes to a fusible link at the starter, it goes to the right (drivers) side of the junction block.
img_5015-png.437403


I would strongly suggest checking over the wiring manuals for both 1984 and 1986 and comparing the bulkhead terminations and verify everything is in the same locations. PDFs of the wiring manuals here
 

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