Just replied to you PM, but now that I've seen your thread I can be a bit more clear!
Looks like you have a Road Rescue with a similar box build as I do. you'll find it's very strudy. The box layout is different. That passenger side box window is great.
For the sake of cash flow, you can do what I did and leave the box and cab white and paint the blue strip (Crimson in your case). Get a decal, preferably custom, and throw it up on the side of the box.
Use the CO2 tank compartment (tall skinny on driver side just behind the driver door) for tailgate canopies and chairs. The compartment behind that is a great bet for a generator. The rear most compartment is a good utility compartment. That's where you store the propane tank, freshwater tank, gray water tank, tools, adapters, extension cords, etc.
Your house (box) batteries are located in the smallest outside compartment on the passenger side, the one all the way to the front of the box and below the larger cabinet door.
If your batteries shut off after 15 minutes, and they're aren't dead (if you cycle the key in the ignition) they are certainly on a timer. This is likely to keep them from draining should the driver/medic shut off the rig and leave the rear power on. There should be two deep cycle batteries in there, and two batteries in your engine bay.
Look around to see if you have a batter maintainer/charger. If you do, when you plug into shore power (the 110 inlet on the driver side) it will charge the batteries as well as power the 110 outlets in the box. If you do not have a generator adapter built in you can simply plug a generator into the shore power when camping or tailgating.
Being in Washington, when you store the rig keep the sliding window on the passenger door open to fight mold growth on the inside.
