Spungen seems to have reached NYC by 1975, when the glam rock scene was already over and the punk scene had started. She had drug problems long before then, though.
Of course, there were girls like her before that time that the glam rockers were fooling with.
http://nymag.com/arts/popmusic/features/51394/
“Nancy was a groupie, trailing after the New York Dolls and the Heartbreakers.”