Is this a real Z/28 and what is it worth?

[DETON8R]

What is the red line on the Tach? I thought Plane-Jane small blocks with a Tach had a lower red line than the SS and Z-28 optioned models. I've heard that the 67's and 68's didn't necessarily have tach's at all when the 302 was an option, I don't know much about the 69's (whether the Tach was a option package when a 302 was ordered) but I'm fairly certain that if a 302 was installed the red line was higher for that option package than the red line for a standard V8 optioned Camaro.