This clip needs to be installed on the bottom filter, 4.25" from the side with the tab. You can see a video showing how to install it (and more) here:
I printed it with PETG since it's more flexible and won't melt in the heat of the summer, but with cabin overheat protection on these cars I think PLA will be fine. It's designed to be printed on its side for tab strength. Enjoy!
The author marked this model as their own original creation.