Once In A While follows three basic chordal progressions. All you need is these three basic parts on which to get the whole score for the whole song.
this part is the introduction (play
3 times). also during the small guitar solo at around 2:00 (play twice).
at the end it is used to build an outro which I will transcribe within
the next few weeks.
this part basically follows a G-D-Am
chordal progression.
this part is used during the verse
('horses run, once in a while...") and the chorus ("once in while, once
in a while for you, once in a while...").
this part follows a G-D-Am-G chordal
progression
this part is used during the bridge
("destiny will have a sense of your touch, once in a while...")
it follows a Em-C-G-D-Am chordal
progresion.