Brian, please slow down I'm taking notes! Let's see, "solar panels on outside of box". Got it.
That's what I was thinking about the toolbox. Everybody makes them, TSC, UWS, etc. and they're on Craig's List starting at around $50.
Batteries and pump in the bottom, and electrical components on the upper sides. Install a couple of 120mm 12V side fans, and you're ready to go. Neat and tidy.
Fixed, I'm poor.