Solid state regulator conversion confusion!

Gentlemen,
You may have followed my painful HEI conversion project last year, that against all odds I never got to work properly. Circling back around, the only thing that I didn't rule out was that I still had a solid-state regulator that was putting out around 14.7 volts. So I'm working on converting it to solid-state with a 70's alternator. Only thing is... It looks like I already have a 70's style alternator... hooked to an old school regulator. This shouldn't work, right? Looking at wiring diagrams for '67 satellite, they only show 1 field wire and I have 2. How do I add the solid-state regulator to my current setup - I have seen the conversion wiring diagram on the forum, my question is where the heck is my field wire on the right (the big one with black tape) going? Is that a chassis ground??
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