Fwd: Justify to both sides

[CieMaKat .]

Hello everyone!

I would like to place custom header for piece, i.e.: hymn number and authors of music and lyrics aligned to both sides of the page:

I tried to do it with fill-line, but then part of the "Lyrics author" goes off the page. Please check a result of the following code:

\version "2.18.0"

\score {
  \new Voice { c' }
  \addlyrics { Al }
 
  \header {
    piece = \markup {
      \line { \lower #2.4 \fontsize #8 \bold "105 " }
      \column {
        \bold "Hymn Title"
        \fill-line {
          \line { Melody author }
          \line { Lyrics author }
        }
      }
    }
  }
}

How can I fix that?

Best regards,

M.Ciesiółka