1958 models have a honeycomb style grille and four vertical chrome mouldings on the bullet-ish body side panel

1959 models have a horizontal pattern in the front grille and taillight panels. The bullet-ish body side features a chrome trim at the front

1960 grille is divided by one large horizontal bar and three vertical bars. Three vertical bars are also on the rear fenders

Information are contradictory in different sources. If you have other information from a reliable source, please let me know.