The header panels are different. 1981 to 1983 take the same and 1984-1987 use the same. Big difference the grille opening area on the 81-83 protrudes out further and has almost squared off edges. Uses a 3 piece grille molding and uses different bumper fillers. 84-87 is more rounded, more areo-dynamic. One piece grille and molding. And of course they use different headlamp bezels and side marker lamps. BTW the park lamps in the bumper are different too. 81-83 uses clear lenses and 84-87 use amber. Eric Fisher