I have seen this song performed live for acoustic and I'm pretty sure this is how he 
it

C/G (332010)
G   (320033)
Em  (022000)
F#m (x24432)
D   (000232)
Am  (002210)

CHORUS:
C/G             G             F#m       C/G
You know I'll wait forever, If I have time to
Am          G                F#m         Em D
But I don't have forever, to wait for you yeah

C/G        G         F#m         C/G
So when I say I want, us to be together
Am           G            F#m         Em   D
Just say you want me too and I'll be yours forever

C/G

VERSE 1:
G      D             Em     D
I could show you a place
G      D             Em         D
You've never been there before
G      D             Em     D
I could show you the way
G      D             Em         D
You just can't go back no more

PRE-CHORUS:
Am        Em          D
I could make you excited     x2

VERSE 2,PRE-CHORUS, and CHORUS all the same notes, song ends on a held G

note: on the switch from the C/G chord to the Am in the chorus, he plays two transition 
that go like this:
e|------0--------------------0-----------------------------------------------|
B|------1--------------------1-----------------------------------------------|
G|------0--------------------2-----------------------------------------------|
D|------2--------------------2-----------------------------------------------|
A|------3------3------2------0-----------------------------------------------|
E|------3--------------------0-----------------------------------------------|