Fretboard and Staff Spacing

[Tom Swan]

Hi Lily Friends! I would like to increase the space between the fretboard
diagram, used here to show a scale fingering, and the top of the staff. I have
tried \paper settings and various overrides with no results. Suggestions please?
Thank you! -- Tom

\version "2.18.2"
<<
  \new Staff {
    \new Voice = "scale" \relative c {
      <f-1\6>4^\markup {
       \override #'(size . 4.0) {
          \override #'(fret-diagram-details . (
                       (orientation . #'landscape )
                       (finger-code . #'in-dot )
                       (dot-color . #'black)
                       (dot-radius . 0.35)
                       (dot-position . 0.5)
                       (top-fret-thickness . 7)
                       (fret-count . 7)) )
            \fret-diagram-verbose #'(
              (place-fret 6 1 1 inverted)
              (place-fret 6 3 2)
              (place-fret 6 5 4)
            ) 
        }
      }   
      <g-2> <a-4> <b-1\5> | 
    }
  }
>>