I just looked at my "1968 Billing History" and the 'Ship to' is blank but the 'Charge to' is 04 / 149. From the link below that would be Fenner Pontiac Inc, 1200 Rockville Pike, Rockville, MD. No dealer advertising on my, at the time, 10 year old car.
Did a search on them and found a Land Rover dealer and Best Buy at that addy.
Don't know if it actually sold there, but I'm sure it did not make it all the way to SC to be sold at Murphy Cadillac-Pontiac in Spartanburg as I had always thought.
Code site:
http://ultimategto.com/art18.htm
DanC