I appreciate the help, and will take advantage of it. (Will shoot you the specific questions directly.) The rear lights sub-harness and the front lights sub-harness is straightforward, and the dashboard gauge lights are pretty easy to figure out. But the rest is pretty confusing. The wiring diagram gives the basic high-level picture, but it is just not clear exactly how a lot of these wires are run, what connectors they go through, etc.
I had put a wiring harness in another project I was working on years back, and it came with excellent instruction sheets that laid out what went where. The Moss wiring harness just came in a plastic bag.
Jim