I've got a 65 GTO I bought back in 1983 that is believed to be a Royal Bobcat. Here is what I know: Was originally bought at the Ace Wilson Royal dealership in MI. Have the original books along with documentation from PHS. Engine is a 421 tripower "SR" service replacement motor, but have no documentation if it was done by the Royal dealership. PHS can't document if the carby jeffs - Pontiac GTO Forum