A.C. 20A blade connector on fuse panel???

[pheengurs]

hey all!

okay, so I'm having electrical issues...

one of many wiring problems I've been neglecting over the years, while I pile on more and more electrical accessories...


so! here's my problem:

years ago, the P.O. swapped out original engine to 350, with HEI, and internally regulated alternator -- but did NOT eliminate the original external voltage regulator.

no prob right? plenty of threads and info out there to help right? well sorta...

there's a couple twists:

-- none of the 4 wires on the external voltage regulator (VREG) connect to the horn relay bus bar as per most wiring diagrams etc that I've seen.

--terminal 3 on VREG has an orange wire, that goes directly into what my stock 64 wiring diagram shows as an empty spot on the firewall connector that feeds the dash wiring... then when exiting that connector on the in dash side, it turns to a pink wire, that plugs directly into a blade connector at top left side of fuse panel called A.C. 20A

or at least, that's how I'm reading it the labelling on the fuse panel... ???

I have no idea why that wire would be plugging directly into my fuse panel, nor what this A.C. 20A blade connector is supposed to be for!

any help on defining what's what on the stock fuse panel, and what this a.c. 20a blade connector might be for, and why someone would run a line from the VREG directly to it???

first pic is of my wiring mess, and you can see the top left red wire off fuse panel, that's the one I'm talking about. second pic is a much better pic of someone's empty fuse panel, and you can clearly see the top blade connector, labelled a.c. 20a, OR perhaps that's for something else, and there are TWO IGN UNFUSED blade connectors?