It's been awhile since I've revisited this thread and wanted to share some info for those who've followed it.
I've constructed a 1/3rd-scale facsimile of the 'template',with concessions to allow for tail lights and license plate.
If I can make it back to DARKO I'll have a chance to capture some numbers for it finally.
I have a half-day reserved for the afternoon of September 15,2017,at DARKO Technologies' wind tunnel in Ogden,Utah,USA.
The model has a provision which will allow me to drop the tail and measure a separate drag coefficient as a truncated half-body.
My truck has had many issues and I'm hoping she'll hold up long enough to get me up there.
Thanks for your interest in the project.I'll try and post data as soon as I can.And hope to capture smoke-flow video to share as well.