You can use whatever type of chord you want to use- though using bar chords are a 
little more intermediate, I think it sounds better.


Start by playing A and D while he's whistling


A                             D
    When I was just a little boy
                        A
I threw away all of my action toys
                   D              A  D
While I became obsessed with Operation

A                                     D
    With hearts and minds and certain glands
                          A
you gotta learn to keep a steady hand
                   D           A   D
and thus began my morbid fascination

E                                          F#m             F#m  E
  Tore the spines from out of all of these self-help books
                                F#m                  D
Made myself a gun that not only shoots but looks so real
                        E                       A     D
Yeah, it shoots through steel with rays of dark matter

 A     D                  A    D 
             Rays of dark matter



It's really just the same through the rest of the song. It's an amazing song and 
easy to learn. I hope you have fun. d:)