3D Printed AC Duct Valve

So I printed and assembled the valve, went to install it, and promptly discovered I’d engineered a square plug for round hole. Or, more accurately a square plug that needs to go through a square hole diagonally. The issue is that I have to navigate an outlet vent to install the valve, and of course I didn’t account for this in the design. So it’s back to the drawing board for what is now version 3