I try to take deep breaths when I run across original 1969 Z/28s. (Deep breath). Protect-o-plate looked correct. “DZ” stamped on engine block pad under the alternator. Owner wasn’t around and it was a public car show, so I couldn’t get too much more nosey. Anyway, gauge cluster on the console, 4speed, vinyl roof, small block, Endura bumper. Sigh, ‘69 Z/28….