The Z/28 emblems came along mid-February, 1968. I have an original '68 Z with a third week of February build date and it has Z/28 emblems.
Are you sure about this? My 68 Z was built the 4th week of February and it has the 302 emblems and not the Z/28 emblems. I believe Jerry MacNeish's 1967-1968 Definitive Camaro Book also states that the 302 Emblems were used through out the entire month of February and the Z/28 Emblems didn't make an appearance until the first week of March. Can someone verify exactly when the 68 z/28 emblems first came along?