When “oh that would be a neat feature” turns into a huge project

OK… that took all damn day….

Ran the new battery cable. Instead of going up the front left wheel well, I went through this hole just forward of my front cage plate. Enlarged the hole a little and used a factory grommet from an old harness.
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Yeah, I need to add some undercoating where the cage plates were welded in.

Cut about 2′ off this really expensive new battery cable.
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Wired the switch per the instructions. Required a couple of trips to the hardware store and one trip to the auto parts store, for connectors, 12g wire, mounting hardware, and some additional 2g battery cable.
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This switch does three things: cuts the main line from the battery, kills the main ignition line (the “run” signal that powers fuse 34), and shorts the alternator through a large resistor to ground, to prevent a damaging voltage spike when the battery connection is cut. That’s why it has so many wires and terminals.

Installed the switch in the dash frame. It’s tight in there, but it works. Used insulating boots on the terminals to ensure no shorts. I’m also going to add a rubber sheet between the switch terminals and the metal dash structure, just to be extra careful.
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Had to cut some stuff off the back of the (now nonfunctional) vent, and grind out the dash frame to allow it to rotate 90 degrees, to increase clearance behind it for the wiring. But will look good when done. Switch in the “on” position…
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And the “off” position…
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Routed the new battery cable from the switch, through the firewall wiring harness grommet. Just need to re-seal it.
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Took me a while, but I finally found the right wiring diagrams and confirmed that the green ignition wire is the one I need to interrupt. Done.
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