There are also panel inserts—often used for screen doors—that don't require any cutting or drilling. Basic dog doors generally have a single flap, ...

The door panel inserts have excess material on the outer edge, so it's necessary to trim as you go. There is plenty of room in the groove, so don't worry about removing too much. See All 24 Photos ...

Check out this Exclusive TMI Products 1965 to 1966 Mustang Pony Interior Door Panels, featuring a door panel reproduction, and OEM feel! Details inside Mustang Monthly ...