thin line for figured bass

[Jean-marc LEGRAND]

Hi list !

I've been visiting the archives to find a trick, but I couldn't find a solution.

I have to insert into my figured bass some thin lines after figures, that 
indicate that the chord is
still running on the note after (am I clear ? ;o))

I've found in the tip and tricks a scheme that could work :

% Generated by lilypond-book
% Options: [printfilename,texidoc,linewidth]
\paper {
    linewidth = 160 \mm
}
\renameinput "embedded-postscript.ly"
\version "2.0.0"
\header {
  texidoc = "@cindex Embedded Postscript
By inserting the @TeX{} command \embeddedps, you can
insert postscript directly into the output.
  "}

\score      {
      \notes
      \relative c''     {
            a-"\\embeddedps{2 7 moveto 5 1 rlineto stroke}"
                  }
      \paper { linewidth = 70 * \staffspace
%     raggedright = ##t
      }

}
 It does print a line from 2 7 to (2 7)+ (5 1). But this line is very thick, 
and I'de like to adapt
this exmeple to thiner lines.

How can I do ?