questions about battery disconnect wiring

@Mattax
I’m trying to decide whether to use this set up, or the one crackedback showed in the other thread.
Questions:
-Could you show a detail of the wiring on the CDR? I can’t tell what goes where on this drawing.
-Please explain what is what in the area of the fuse box. Is that existing wiring? What is that thing that sort of looks like a headlight switch?
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