Evan-
I am unsure of your desire for the absorption (gas) refrigeration. If you have the room, I would go for 2 Engel's, one to use as a fridge and one to use as a freezer, with remote monitoring temperature gauges it would be easy to set up so that you can monitor the temps from the cab. Also the emissions off the gas may be a concern as well. As you can see I am trying to lean you to the compressor driven units, on top of that they will work with a 24v system as well as 12v, so you could keep them removable and use in your daily drive for trips to the grocery store, ect. You can also use solar power and with that size you can go hard mounted for cheap.
It sounds like you have an exciting build up underway, and it will be fun to watch.