HOTRS came out in Sept '64, and clocked in at just over 4 minutes (so I'm probably wrong about the three minute thing.) Like A Rolling Stone was the longest single released at the time. (all according to the web)
Check this site out for some interesting singles trivia (amaze your friends - and bore the pants of others - at your next party.) http://www.everyhit.com/record7.html It reackons Harry Belafonte cracked four minutes in the fifties. Don't know if he qualifies as a pop/rock act though. And SOS by ABBA is the only palindromic hit by a palindromic artist. Go figure.