Nic, You asked for an ammo can 12v power station build walk thru.....this is about the best I can do.....at the end is a generic Amazon Parts List the stuff I mention.
First you need to decide what you want it to do. Just to be a USB charging station? A combo power station with USB charging as well as to power a HAM radio? Do you want it to be charged by a separate battery charger only? Or do you want it to be charged by solar panels? How much power, or amps, will you draw from it? The more you want it to do, the more stuff you need, the more it will cost, and the bigger the enclosure you will need. After you decide on what you want it to do, you have to figure out what enclosure you will use. Using a FAT 50 GI Ammo Can like I did, also limits the size of battery you can use. To help you decide on the enclosure, you need to decide on how much energy you need. Since this will be a 12v system, look at the physical size and the AH rating of the battery. Bigger AH is better.....as long as the battery will fit..... Gonna make some assumptions for this walk thru... FAT 50 GI Ammo Can USB Ports Cigarette Lighter Socket Anderson Power Pole connectors for HAM No Solar Charge Controller SLA battery
It will be an external access build. 10-15 amps total draw. I use the 1” modules for my builds.

If you get this set, and use each module, you will have to 5 holes in the lid of the ammo can. Because for powering a HAM radio, you will probably need Anderson Power Pole connectors. You can get them in a 1” module as well.

But, if you replace the Voltmeter and USB charging modules with a combo module, you only have to drill 4 holes.

To drill the holes in the ammo can lid, I drill a pilot hole with a regular 1/4” drill bit. Then I use a step drill like this one to open it up to 1-1/8”:

I then use a round file to clean up the burrs. As you can see here, four holes don’t look bad on a FAT 50.

I placed the round nuts from the modules on the lid in several configurations. Because my goal was to have 3 USB charging Modules, and 1 Cigarette Lighter Socket, I decided on a straight line. When I build my next FAT 50 with external access, it will be a combo. And I already know I’ll do two above and two below the handle. Towards the corners.
Before you drill the holes, ensure you don’t get too close to the edge so that you avoid the angled metal that holds the gasket. Don’t want to interfere with the modules nut.

My next one will have the Power Switch and USB/Voltmeter modules above the handle. And the Cigarette Lighter Socket and Power Pole modules below the handle.
But you gotta figure out how YOU want them arranged.








But Wait! There’s more. If you don’t want to drill holes in the lid of your ammo can, you can cut a piece of this plywood or lexan.....I used lexan with one, trimed it to fit the body, then put a bead of hot-glue inside at the depth I wanted it to be.....just deep enough to clear the modules when the lid was closed.....this kept it waterproof.....
I recommend using a shelf as is much easier to reconfigure later, or even start over without having drilled hole in the can itself.
After you drill and de-burr the holes, you get to play with deciding on the arrangement of the modules.
Once you have them arranged the way you want, insert them and screw on the nuts to lock them in place. But Wait! There’s more. If you don’t want to drill holes in the lid of your ammo can, you can cut a piece of this plywood or lexan.....I used lexan with one, trimed it to fit the body, then put a bead of hot-glue inside at the depth I wanted it to be.....just deep enough to clear the modules when the lid was closed.....this kept it waterproof..... So everything described above also applies to drilling a shelf for inside the can....
Next, you get to start wiring it all up...But first...if the assumption is 15 amp max total draw, you can use 14ga wire. But you need 12ga wire for up to 20amp max total draw. If you need more than 20amps, this build will need some important changes
I choose to use “Flag” connectors to save some length at the bottom of the module. See the picture above that shows them. Here is the basic wiring diagram for the modules:
