I like what you did on the front end, but I strongly recommend that you not try to pull too much amperage through a cigarette lighter plug. They, technically speaking, suck. They are NOT intended to run anything but the smallest inverter. I literally smoked the one in my subaru -- the thermal fuse ... fused. I don't think you can fathom the hell that is driving across Utah without any MP3s...
So, instead, we did a cheap-o Wal*Mart fuse block under the hood, and 10ga wire to the cab.
In the cab, we've got a number of Anderson Powerpole connectors, which are sort of the standard for high-amperage DC connectors. One set goes to the radio (which you can't see in the picture), the other set goes to the set you can see coming out of the VX's computer 'wart'. Below that, you can see my inverter, a number of pigtails, extensions, and adaptors. On the right is a set of cigarette plugs for small loads like phone chargers, etc.
Powerpoles are genderless, any one of those plugs can be used backwards. In a pinch, I could use an extension + the aligator clips plugged together to make a ghetto set of jumper cables. Or, I can adapt someone else's cigarette lighter to powerpoles, and plug in my equipment.
On the left are a couple more Powerpole ends, and the additional bulkhead connector that I intend, one of these days, to put in that back panel, just like you did. I'm hoping to just run 8ga + to the back, and return through the frame. How hard was it to get wires up to the back?