Thank you both! That's a big help.
One thing I have not located yet (haven't looked) is the source vacuum line, red, which as I understand should be around the carburetor.
I see that harness kits are available; it's hard to tell from the picture if they're color coded. I'd like to keep them the same if I go that route, as it's made troubleshooting this a lot easier.
I've also read up a little on the Posi-Lok, just a cable that runs from cab to axle.
Billy, you are describing something different. I'd have to see what one looks like.
Will that work on my YJ?