ChiefB
Here is how I hooked my ammo box with USB, voltage and cig lighter spot. In the bottom of ammo box I put a 24-12volt transformer and fuse block, on top of these items I built a false bottom with 2 small "eye" hooks in opposite corners to lift false bottom for access to electronics. On top of false bottom I keep my paperwork, a few small tools and spare bulbs, my 9mm is on my hip. Next ammo can/usb set up I plan to go with 6 place holders (2 x 2 usb, 1 cig lighter, 1 volt gauge, 1 power switch and 1 extra just in case. On top of ammo can is a blue tooth speaker, it is loud enough to hear with driving.
Hope this gives you more ideas.
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