Adjusting initial LH barline

[Peter Chubb]

Hi,
        I'm trying to update Arbeau's Pavane at Mutopia.org.  I've
        got it almost ready, except for two things.

        The drum part in the original is on a separate staff above the
        system containing words and tunes.  There is *no* connecting
        line between the main system and the rhythmic staff.

        How do I do this?  I've tried removing System_start_delimiter,
        but still see part of the line.  

        Here's a small extract from my current effort; I want to get
        rid of the thin line that tries to connect the ChoirStaff with
        the RhythmicStaff.


\version "2.12.2"
recscore =
\context StaffGroup \with {
  \remove "System_start_delimiter_engraver"
  \remove "Span_bar_engraver" 
} <<
  \context RhythmicStaff = "tambour" {
    \override NoteHead   #'style = #'cross
    \stemUp
    f4 f8 f8 
  }
  \context ChoirStaff <<
    \context Staff = "descant" {
      \clef "G^8"
      a''2
      \bar "|."
    }
    \context Staff = "treble" {
      \clef "G"
      a'2
      \bar "|."
    }
  >>
>>

\score {
  \recscore
  \layout {
    \context {
      \RhythmicStaff
      \override Clef #'stencil = ##f
      \override TimeSignature #'stencil = ##f
      \override StaffSymbol #'stencil = ##f
      \override BarLine #'transparent = ##t
    }
    indent = 0.0\mm
  }
}


--
Dr Peter Chubb                                  peter DOT chubb AT nicta.com.au
http://www.ertos.nicta.com.au               ERTOS within National ICT Australia
All things shall perish from under the sky/Music alone shall live, never to die