Well, I moved the amps to the rear auxiliary batteries. Now I should be able to park for hours, at least I would hope so. If I take off this weekend, it's easy enough to hook up an inverter to the aux batteries too. Also, even if I run the batteries dead, I should still be able to start the truck. I might put two of these in. One for the main battery and one for the auxiliaries. This way I can watch the voltages. For $12 it's hard to wrong. Might be a touch bright.. maybe use window tint to darken/adjust them a bit. I have two blanks in the dash. They'd fit nicely there.
https://cimg3.ibsrv.net/gimg/chevrol...2a8e53b28d.jpg

Remember to check/take your jump box/fire extinguisher, just in case.

There's already one for your main battery in the cluster.