On my promotional model boxes it reads: "Putting You First...Keeps Us First on the 1969 boxes. On the 1970-71 boxes it says: "Putting You First In a Big Way." On my 1972-73 camaro boxes it says: "Building a Better Way To See The U.S.A." I have a 1970 camaro box that also reads "The Sporty Ones" by Chevrolet. These boxes are originals from Chevrolet for their Promo models in those years. I would say the slogan for their USA-1 plates would/should be the same as their Promo boxes.
