Push out air vent

The Kawasaki Mule UTV that I drive has an enclosed cab, with a fixed, lexan windshield. As the temperatures are currently running over 100 during the day, and there's no air flow moving in the cab, I decided I needed some air vents.

These vents are loosely modeled after a version that is commonly installed in small aircraft. They are flexed into a hole in the window, and then they can be closed or pushed out into the airflow. There is a hole in the reinforcing rib. I used 550 cord to give me