GTS or GSS

A quote from Street Muscle magazine. 12/29/2012
"And, like the 1967 Dart GTS 383, the 1968 Dart GSS served as inspiration to Chrysler because, for 1969, Chrysler released the 440 as a regular factory offering for the Dart GTS (as well as for the Plymouth Barracuda). Dodge built 660 GTSs with the 440, giving the rest of America the opportunity for an overpowered compact. It would be another two years until Mr. Norm would offer another unique car with the 1971 Demon GSS, but the 340 Six-Pack didn’t inspire Chrysler the way the GSS did."