Starting to run out of room, lol.
Starting to run out of room, lol.
Here we go again…
Update 2
Just got two 9V batteries, the LED, and alligator clips, and figured it out by trial and error.
EDIT; update: https://www.amazon.com/dp/B074FSZWVT/
I believe that should work for this. If not, I suspect I'll find out soon enough, and then find some other use for them eventually.
Weird, really specific thing, I know.
Okay, so I got a pair of rocker switches for my button box, that are red and amber, to correspond with the red and amber lights I already have. The red light isn't installed yet, but it's identical to the amber one that is (except red, lol). The amber light is already used to indicate power going to the entire box from the other battery (separate from the truck's electrical system entirely). So, and this gonna be kinda weird: I want the red light, and only it, to turn on whenever power from the truck itself is lost.
I probably want some kind of relay, which I'm assuming probably exists, hooked up to the cigarette lighter from the truck, and the red light (which, again, is fed by the other battery).
How do I do this? 
Buy irhapsody 5 Pack 40/30 AMP 12V DC Waterproof Relay Kit with Heavy-Duty Pigtail, 5-PIN SPDT Automotive Relay: Accessory Power - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
Okay, so, my button box works. I have an independent toggle switch for the backup camera itself, and another one for the screen. AND THE LIGHT FOR THE KILL SWITCH IS WAY TOO BRIGHT. Gonna dig through my stuff and see if I can find a potentiometer for it, and if not then I'm gonna either scavenge one or buy one. I can't have this.
Distribution panel with a fuse and a blue light (to indicate "on") for every switch, a kill switch, and an amber light to indicate that the kill switch is turned on.