This song is done by Roger (Louis St. Louis) and Jan (Jamie Donnelly) backs up.
The lyrics are based on the movie, not the stage production.

Intro: NC (piano appegio F)
F          Bb      Gm
I spent my da-a-ays 
     Eb               F               Bb7 Bb  Gm
Just moo-oo-oo-oo-oon-ning so sad and blu-ue 
           Eb
So sad and blu-ue
F          Bb        Gm
I spent my ni-i-ights 
     Eb               F             Bb7 Bb    Gm
Just moo-oo-oo-oo-oon-ning all over yo- ou
          Eb     F
(All over who-o?)

[Jan harmonizes from the second words of the following, starting from Eb, her
notes move up a tone with every second chord change.]
     Cm7            F
Well I'm so full of lo-o-ove 
   Dm          Gm       
As any fool ca-an see
       Adim         D7
'Cause an-gels up a-bo-ove 

[Jan stops harmonizing from this line, piano plays the intro on 'moon']
     Gm NC       (F)
Have hu-u-ung the moon o-on me
                                         Bb
                           (Why must you go-o-o)
           Gm                                 
Why must I go-o-o
     Eb               F7
Just moo-oo-oo-oo-oon-ning
         Bb7 Bb     Gm 
So all a-lo- one 
          Eb    
(So all a-lo-one)

F              Bb
There would be no-o-o 
                Gm
(There would be no-o-o)
     Eb               F7
More moo-oo-oo-oo-oon-ning
       Bb7     Bb     Gm          
If you would ca-all me
           Eb      F
(Up on the pho-one)

[Jan harmonizes from the second words of the following, starting from Eb, her
notes move up a tone with every second chord change.]
      Cm         F  
While lying by myself in bed 
  Dm            G
I cry and get myself the red eye
BOTH
Cm7             F7                Bb7 Bb
Moo-oo-oo-oo-oo-oon-ning  o-o-ver yo- ou

[Bass and trumpet play D,Eb,E,F, guitar rings F chord]

[Accordion rings, and piano appegios F7 chord when 'stand' is held]
     NC        
I'll stand 
[Bass, guitar rejoins on [-hi-]
   Bb
Be-hi-i-ind
                Gm
(You'll stay be-hi-i-ind)
    Eb               F7
You moo-oo-oo-oo-oon-ning 
        Bb    Gm
Forever mo-ore 
         Eb  
(Forever mo-ore)
F               Bb 
Some-day you'll fi-i-ind
                Gm
(Someday you'll fi-i-ind)
   Eb               F7                 Bb7  Bb  Gm
Me moo-oo-oo-oo-oon-ning at your front do-o-or
             Eb
(At my front do-o-or)
F
Whoa, 

[Jan harmonizes from the second words of the following, starting from Eb, her
notes move up a tone with every second chord change.]

Cm             F          
Every-y-day at school I watch ya
Dm               G
Alwa-ays will un-ti-il I got you 
Cm7 (ring)      F7 (ring) 
Moo-oo-oo-oo-oo-oo-oo-oo-oon-ning
Cm  Bb (ring)
Too-oo
There's a moon out tonight