Here is a photo showing a 1969 Camaro RS/SS Z11 convertible going down the dragstrip during the pre-race ceremonies with a woman on the back prior to a large NHRA sanctioned event at Maple Grove Drag-O-Way in Mohnton, Pennsylvania sometime during the racing season of 1969. Notice that most of the people in the background are wearing pants, long sleeve shirts and jackets. Either it was a cool day in the summer or possibly spring or fall. Also notice the "USA-1" license plate on the front, the Uniroyal tires, the small Chevy bow-tie sticker above the rear wheel and the extremely poor fitting lower part of the door decal.
I found the photo years ago on Ebay.