Now, where have I seen that photo before?
It looks like it was posted on Camaros.net back in 2007. 169Indy wrote: "I have a GM photo, copy (SCANNED) of the 68 Z28 engine bay photo that was printed in the Camaro Enthusiast a few years ago and rarely see people reference it with regards to details. Appears to be a Norwood car as evidence by the PTB stampings."
Ed Bertrand posted the picture for 169Indy.