[freebeard]

Could you post the graphic at 1:39 as a still image? For posterity.

This is relevant to my interests, I paused the video and went out and measured my Dasher 3-door: 28°. I'm hoarding some textured aluminum sheet big enough as needed, I've been thinking about a J-shaped edge that would slip over the whole hatch on three sides. I don't envision a problem with visibility.

I'd been thinking about rear-slanted 'D-pillar spoiler's. This confirms it. I think of it as a boxed cavity. Looking forward to the diffuser part.

It's radiator is next to the left front wheel. Twice as good, but half as much, air curtain?

The active spoiler might be helpful with two positions, eco and airbrake. Sort of a third brakelight semaphore. I wonder how to get that without drilling glass or metal.