zenob437 is still trying to sort it out
Awesome.
I envy you.
How I did it: Finally just booked the flights. Other commitments be damned. The other details fell into place. Was very much worth the trip and the experience. Cambodian people were lovely, fun and savvy.
Lessons & tips: The Cambodian airport has the 'visa on arrival' process efficiently honed to a fine art. Don't bother with embassies and queuing. It took less than five minutes total for us. Really. We timed it.