Full credit should go to JamieParkinson for such great work on the original tab.  
I just super-simplified it into chords so I hope I did their tab justice.  Enjoy.

Intro: (2x)
C (x32010@1) G (320003@1)Chorus:
                   C (x32010@1)              E7 (020130@1)                    F (133211@1)                       G7 (320001@1)Why do you build me up Buttercup baby just to let me down and mess me around 
                  C (x32010@1)                   E7 (020130@1)                          F (133211@1)                G7 (320001@1)And then worst of all you never call baby when you say you will but I love you still 
            C (x32010@1)                     E7 (020130@1)                    F (133211@1)                      Fm6/D 
I need you more than anyone darlin', you know that I have from the start 
      C (x32010@1)                G (320003@1)                              F (133211@1)        C (x32010@1)    
So build me up Buttercup. Don't break my heart

Verse: 
            C (x32010@1)        G (320003@1)                  Bb (x1333x@1)            F (133211@1)               C (x32010@1)             F (133211@1)I'll be over at ten, you tell me time and again but you're late. I wait around and then
  C (x32010@1)              G (320003@1)           Bb (x1333x@1)                    F (133211@1)                C (x32010@1)              F (133211@1)I went to the door and I can't take no more but it's not you. You let me down again

Pre-chorus:  
Dm (xx0231@1)                  G (320003@1)             E7 (020130@1)          Am (x02210@1)      
Baby Baby try to find a little time and I'll make you happy 
F (133211@1)                             D/F# (200232@1)                         G (320003@1)              G7I'll (320001@1)be home waiting beside the phone waiting for you.

Chorus:
                       C (x32010@1)              E7 (020130@1)                     F (133211@1)                       G7 (320001@1)Why do you build me up Buttercup baby just to let me down and mess me around 
                   C (x32010@1)                 E7 (020130@1)                       F (133211@1)                     G7 (320001@1)And then worst of all you never call baby when you say you will but I love you still 
            C (x32010@1)                     E7 (020130@1)                    F (133211@1)                              Fm6/D 
I need you more than anyone darlin', you know that I have from the start 
      C (x32010@1)                G (320003@1)                           F (133211@1)        C (x32010@1)    
So build me up Buttercup. Don't break my heart

Verse: 
       C (x32010@1)        G (320003@1)           Bb (x1333x@1)            F (133211@1)       C (x32010@1)                      F (133211@1)To you I'm a toy but I could be the boy you adore, if you'd just let me know
    C (x32010@1)                 G (320003@1)              Bb (x1333x@1)        F (133211@1)           C (x32010@1)                   F (133211@1)Although you're untrue I'm attracted to you all the more. Why do I need you so?

Pre-chorus:  
Dm (xx0231@1)          G (320003@1)             E7 (020130@1)               Am (x02210@1)      
Baby Baby try to find a little time and I'll make you happy 
F (133211@1)                           D/F# (200232@1)                                   G (320003@1)              G7I'll (320001@1)be home waiting beside the phone waiting for you.   Ohhhhhh

Chorus:
                   C (x32010@1)              E7 (020130@1)                     F (133211@1)                       G7 (320001@1)Why do you build me up Buttercup baby just to let me down and mess me around 
               C (x32010@1)                     E7 (020130@1)                        F (133211@1)                     G7 (320001@1)And then worst of all you never call baby when you say you will but I love you still 
         C (x32010@1)                     E7 (020130@1)                 F (133211@1)                              Fm6/D 
I need you more than anyone darlin', you know that I have from the start 
      C (x32010@1)             G (320003@1)                             F (133211@1)        C (x32010@1)    
So build me up Buttercup. Don't break my heart

Chords:  (The more obscure shapes in the chorus)

E7 (020130@1)            x20100
G7 (320001@1)            x20001
Fm6/D           xx0111
G (320003@1)             3x0003