The gap-filler window is on the road, although I might need to remove it for the road-trip at the end of this month, not sure yet. However, here's the car in full boat-tail-configuration:
I forgot to mention; I also painted the hitch box lid black, since that is the component that sits in the reflection in the boat-tail windows. The darker and more matte the lid, the less interference you see in the windows.
An idea how it's built and attached:
The screws go through the hinges into jack-nuts installed in the acrylic. (I have to look up on Mcmaster to see if I'm remembering the right name: also called screwdriver-installed-rivet-nuts.)
The cut you see was needed to 'shrink' just a bit, as an adjustment to get the piece to mate with the Kammback.
I decided the gap-filler-window needed to be totally transparent. So then how do you heat the acrylic (PMMA) to bend it? Last time I tried a heat gun, and it took forever. This time I used a little propane plumbing torch. Easy!
An idea what the view looks like, from the point of view of the driver (turned to the left, like if you were backing up):
There is potential trouble with cold precipitation, which I'm expecting on this road-trip, so unless I'm really on it and get a 12V defroster contraption wired up, the gap filler will probably sit this one out. Also, being acrylic, it can't be scraped for ice (I checked with a piece of scrap - it got scratched up).
Apparently I didn't shoot these so you can tell, but I'm pulled just off the frontage road not far from the Salt Lake, there's a rather flat segment of a couple miles with newish pavement - a rather good place to coast-down when the wind is down (which happens here and there).
Unfortunately the GPS did something bizarre and the data is more-or-less garbage:
You might think this is something I could process my way out of, add some smoothing, or cut the weird points, or better yet if I could find evidence of the phone's clock skipping around. I looked at the raw data closely and couldn't see any neutral way to reprocess. I think this is the first time I've captured GPS with the music player running, maybe that's at fault. There may be ways to get better GPS data with a different app (this was MyTracks). I've also got a low-end bluetooth OBDII dongle and the Android Torque app, so I've tinkered a bit with the OBD speed sensor, which outputs an integer km/h. Unfortunately I haven't got the too-cheap knock-off ELM device to delivering reliable short polling intervals - in other words, rounding would be fine if the polling interval could be minimized so I could get an accurate time stamps on the km/h splits, but otherwise it's a mess.
Thinking it's about time to go to the robust DIY solution: a bicycle computer.
But I'm probably just going to focus on the wheel skirts, grille block, maybe air dam for now. Back to testing and fine tuning my boat-tail later.