Here is something. Screened vents.
Custom fit for Transit Vans. They will roll up in the tops of the front windows in the van when we’re parked. On their own, they won’t do much for airflow or a cross-breeze, but when the roof exhaust vent is installed in the back, these will be where the air comes in that will get pulled through the car, cooling us down to the ambient temperature outside. That will be good airflow. No bugs. Good sleeping weather.