My apologies, folks. I may have incorrectly assumed that, after turning off the pump, that the running engine would continue to evacuate the RV antifreeze that was pumped into it. Apparently, this is not the case.
To answer my own question...
Start the engine.
Start the pump (to push the rv antifreeze completely through the system).
Stop the pump.
Apply fogging oil to the air box (to choke the engine out).
The entire process should take no more than 2 minutes per engine.
If this is wrong... please feel free to stop me!