Somewhere around 1963 through 1971 the pentastar was placed only on the right fender...presumably on the curb side for identification. All Chrysler built cars got this. If memory serves it was a new corporate logo that needed exposure.
Some say it went later into 1972, but at least my '72 Plymouth did not come with one. The pentastar has pins on the back that go into holes on the fender, so I'd assume cars later than 1971 that happened to get a pentastar had a 1971 "left-over" fender put on at the factory.
