Yes, I realize all this. All 73 Rivieras were built at Flint, along with other full size Buicks. The full VIN has the info as to body style, what model, engine, etc. If a listing exists of all Buicks built at Flint in June and July of 73, then I would just work from the last one back, counting only the Rivieras till I got to my VIN. If this list doesn't exist, then if someone has a 73 Riviera with a VIN higher than the last 6 digits of mine, then their data plate and build sheet info would be helpful to me. The last week of June 1973 was a full week, Monday through Friday, and I don't know what day of that week mine was built. I also had one reliable source tell me that no Rivieras were built in July 1973.