Early production '69s at Norwood [to approx. N520xxx] with non-black interiors had a VIN tag painted to match the dash top. Black suede afterwards. I don't know if Van Nuys did that.
The last 6 characters of the VIN were assigned when Chevrolet received the completed body from Fisher. The 'con VIN' [ex. 9N500001] was stamped in two areas into the freshly painted cowl. The body was then routed to a spot in the Schedule Bank to await release to assembly. The VIN tag was installed at the first stop, the Trim Line. Since the windshield was already installed, the rivets were installed from under the dash, the rosette heads technically upside-down. VIN sequence had nothing to with scheduling; cars were not built in strict VIN order.
Later on when the foam rubber dams were glued to the cowl panel, workers smeared rubber cement over the cowl top con vin as a rust preventative.
http://www.camaros.org/assemblyprocess.shtml