I never thought of it like that, those vent windows have been around a long time. I want to make window blocks that are much taller to get more flow out of them. I just haven't taken the time. When I do make them, I will do a writeup on them, maybe people would be interested.
As far as the transition goes, I will have to look at how you did the cardboard kammback again and try to mimic that. I thought you had one angle... working with Coroplast makes arcs hard and angles easy... I guess it's the price you pay for cheap. Maybe I can make "Phase I" the 10deg slope with the trunk able to open, and "Phase II" a 15deg extension that goes further back the vehicle... I actually like this idea a lot...
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