Jack Bruce - Theme For An Imaginary Western Chords

The chords I could get by ear. Since I needed the chords written and I couldn't find any
score nor tablature for this song, I posted what I could get. NOTE: The "?" is a chord
which I'm sure it's there but I can't figure it which is it. It's the same chord through 
the whole song. Any corrections is welcomed.

INTRO: G Bm Em

         G     Bm         Em
When the wagons leave the city
         A                  F
for the forest, and further on
         G    Bm      Em
Painted wagons of the morning
       A                    C
dusty roads where they have gone
          G        Bm           Em
Sometimes travelling through the darkness
        A             F
met the summer coming home
        G   Bm      Em
Fallen faces by the wayside
          C        ?         G     Bm
Looked as if they might have known

      Em         Bm
O the sun was in their eyes
      Em            Bm
and the desert that dries
       C       G
In the country towns
          A        Em      B C
where the laughter sounds

      G      Bm       Em
O the dancing and the singing
      A               F
O the music when they played
      G    Bm         Em
O the fires that they started
      A             C
O the girls with no regret
      G                Bm
Sometimes they found it
               Em
Sometimes they kept it
      A              F
Often lost it on the way
            G    Bm     Em
Fought each other to possess it
         C       ?        G   Bm
Sometimes died in sight of day

      Em         Bm
O the sun was in their eyes
      Em            Bm
and the desert that dries
       C       G
In the country towns
          A        Em      B C
where the laughter sounds

OUTRO: G Bm Em A F G Bm
Em C ? G