\version "2.19.47"

\include "watermark-timesig.ily"

music = \relative c'' {
  \time 7/4
  c1 c2.
  \time 5/4
  c2. c2
}

\score {
  <<
    \new StaffGroup <<
      \new GrandStaff <<
        % Add a watermark time signature top-aligned to this staff
        \new Staff \with {
          \watermarkTimesig 10 
        } \music
        
        \new Staff \music
      >>
      \new Staff \music
    >>
    \new StaffGroup <<
      % Add a watermark time signature top-aligned to this staff
      \new Staff \with {
        \watermarkTimesig #'(.8 .9 .3) 16 
      } \music
      
      \new Staff \music
      
      \new GrandStaff <<
        \new Staff \music
        \new Staff \music
      >>
      
      \new Staff \music
    >>
  >>
}