That looks very similar to the connector I noticed on my old Vetter fairing. . .
As far as the jumble o' wires goes, I was looking at the same thing on my bike courtesy of APO (©Terry from Australia for '***hole previous owner) . .. soooo after many moons of frustration with bizarro wiring problems, I ended up going through the whole wiring, pretty much. I cleaned all the connections with a small round wire brush (a .22 cleaning brush, I think?) and I used dielectric grease on them all on reconnection. I found several connections that weren't snapped in place, as well as sporadic verdigris (green corrosion).
The real catcher was the rear tailight hot wire (brown) that had worn through and was grounding out on the fender. I kept wondering why my battery would die on long rides even though everything tested fine when I would trouble shoot it. Well, I wasn't trouble shooting with the headlight/tail light on. *duh*
Since someone has gotten into that wiring and did some wiring mods, I would be double checking against your wiring diagram, maybe redo it stock. . .neva know. I saw a VW van once that the radio went on and off with the turn signal because of some idiots wiring. . .LOL.
*good luck* old wiring can really suck sometimes. . . . .
