Non GT that run on the rockers. When did first come out? Dealer installed?
It looks like the introduction of rocker stripes available through dealers lagged several months behind the official introduction of the factory GT package in April 1965. The May 1965 Merchandising News indicates fog lights, tail pipe extensions and GT badges were available, but states "Triple Accent Stripes will be available soon. Details will be published in June Merchandising News."