Alternator & Starter wiring question

[Travis1960]

I am piecing back together a '73 GMC that was apart when I got it. The engine is just about ready to go back in.





Before I drop the engine in I need to get the wiring straight. At some point in time the pickup had an HEI distributor installed. So it is no longer a "points" system. This first image shows the wire loom at the alternator. The plug and red wire with round terminal are easy enough, but there is a mustard yellow wire that terminates here, the one at the tip of my finger in the image. Where does this wire go?





Now, following the wire loom on down to the starter. The large red wire is obvious, it goes to the large stud on the solenoid. That leaves a brown wire, a black wire and two mustard yellow wires. One of these mustard yellow wires goes along the frame back towards the fuel tank. I assume that is the fuel gauge wire. So, that leaves one black, one brown and one mustard yellow wire at the starter. Where do these three wires go?





Thanks for any help anyone can provide.