To try to answer your original questions, below is a pic of mine to give an idea. Right now I have only a terminal connected for testing electrical so the big fat wire going to the starter is missing. Also ignore the wire and connection in the foreground. That is for a battery tender. Also, on the back side you can just barely see a little bit of a big fat wire that is for my stereo amp which is obviously not original.
What is left are four wires that are bundled into two pairs that terminate. One pair of wires routes through the firewall and up the tunnel. The other routes over to the relay board. One of the wires running to the relay was originally 2.5mm (13 gauge) and the rest were originally 4.0mm(11gauge). The two ring connectors connect to your little mystery connector. The large bolt on that connector replaces the through bolt on your lead battery terminal. Then the ring connectors attach with the allen head bolt.
Thanks for showing me that is supposed to be allen head BTW, now I have something else to change
Hey, if you get a chance, could you snap a pic of the hole in that connector with the allen bolt removed? I have the 914Rubber repro of that block and just curious what the original looks like inside.
Looks like yours is wired right but somebody has spliced in larger wires with crimp butt connectors.
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