Thanks for the good sense.
I ended up going through a lot of past threads here on the Bolt and mudding through. Jack Sweeden's "How to Wire Your Streetrod" helped. Believe it or not, this one's just about ready to fire up.
Part of the problem was that the harness came with a bunch of splayed out different-length wires from two directions with connectors to where a fuse box would go. They didn't match to any box I could find. And the connectors were too big. I ended up cutting and splicing the wires to connect to a standard fuse box. I wonder why the harness-maker didn't just leave foot-long or so unfinished leads to connect to the box?
Anyway, it gave me something to cuss at when things seemed to be going too easy.