There were a lot of books out there in 1965. I think most of us started out picking out melodies along with records and progressed to learning A, Am, C, D, Dm, D7, E, Em, G, G7. The real break throughs came with adding barre chord forms. I had a bit of advantage in being a play by ear violin player from the time I was 4 or 5 years old. For me the real break through was the Mel Bay Orchestral Guitar Chord book where I learned the chord form built around the open D. This enabled me to develop runs up and down the neck. It was probably my 2nd or third year of playing when I made this leap.