[bigblockpace]

The first documented use that I have found on these plates was on the Pace Car replicas.
Actually there is also a Patch that was found on all the hats used by the Pace Car Crew that was also described as a 1968 item.
My thoughts are in line with other collectors that feel since the Activities that Chevrolet was handling for the Pace Cars were supposed to be the cutting edge at the time, that Chevrolet used a number of things at the 1967 Activities that most originally thought were known as 1968 items.