Interesting... look forward to hearing more about this.
I went stealth with a portable instead of window unit. I put the licence plate on a hinge and then vented the A/C under the plate.
Power is not too bad. It hits 15 amp when the compressor comes on, but after that it is 5 amps. It will run on my Harbor Freight 1500 watt inverter. Just start the A/C with the van engine running. Then set the temp so low the compressor will never go off again and you can turn off the van engine and let the batteries do their job.