Sorry for the delay on my own thread. We were without the rig for several weeks due to warranty work.
Check Engine Light. "known issue". blergh.
Thanks everyone for the ideas. We have tabled this one until the weather is cooler (and we'd want to sleep with the windows open. That means adding a screen, too.) It would be nice to help us cool down the rig on departure day, but we're doing okay with that.
Someone asked about how the window locks...and now that we have her back, yes, there is a metal piece there that we could use.
Thanks for all the advice, ideas. I think I know how I want to do the prop (from PVC). I'll need to think on a good velcro/similar screen that can still break away instantly for egress.