Originally bought by your grandpa is excellent provenance if the car has been in the family the entire time. Maybe there is purchase/dealership paperwork and old pictures to further add to the provenance?Hey guys, I stumbled across this thread while researching Petty Blue Belvederes a while back and finally decided to join the conversation. I have one of the few known to exist 1966 Petty Blue Belvedere II's with the 999 Paint code. My grandpa bought it new in 66 and and we have restored it over the past few years.