Flickering Lights

Have, I hope, given information that I uncovered today after stripping tape off of wiring harness. Got a big mess on my hands. Trying to follow all the different color changing wires has been fun! Guess I will have to get my wire out and do some more rewiring.
Still would like to know why Blue wire cut at alternator and connected to terminal at bulkhead connector was for or even went to. Would it have been connected to battery terminal of alternator?