In the end the birds were way overdue for processing and we had just gotten to the point where we really figured out how to quickly go through the process; however, we burned out the drill we were using for plucking and we were about to leave for vacation.
We decided to try a local-ish processor, Twin Cities Pack, for the remainder of the chickens. So early one morning we loaded them up into a bunch of crates in the back of the farm van (fortunately the kids were both away at camp) and set off for Janesville.
Then the next day I went back with a bunch of empty coolers
and came back to fill up our chest freezer: