Keep in mind the little pentastars were not on both fenders, only the passenger side.
Original passenger side fenders have two small holes to mount the pentastars. The pentastars have 2 pins on their backside that are used to install on the fender.
The lower dogleg of the fenders were rust prone and the pentastars were often lost during bodywork to repair the rust. Also, if the passenger fender was replaced, lazy body shop guys would often just fill the holes prior to painting rather than order up a new pentastar from a dealer.