We proved that forcing cool air down the Service Plug port does cool the battery pack. We also proved that using the air conditioning system to cool the air going down the port is not very efficient, the faster charging rate we get because of the cooler battery is eaten up by the power consumed by the AC compressor motor. So the question begs to be asked, "How can we more efficiently cool the air going down the port".
The answer is obvious, find some way to cool the air besides using the AC system. I can think of several ways to do this. One way might be to use a ice chest as an ice filter and force the air through the ice chest before the air goes down the port.
Another way might be to use one of those large chemical spray bottles to spray ice water down the port. You could use a mist nozzle so the spray pattern is even going into the port. You can even get a battery powered spray bottle that you could rig up to spray while you are in WalMart getting more water and ice or while you are driving down the highway.
I'm not planning to try any of these ideas any time soon but I can easily see how someone planning a trip across the desert Southwest in the middle of summer might seriously consider some alternative method of cooling. Hopefully if anyone does try some form of alternative cooling they will provide a post so we can benefit from their experience.