Hairpins in Polyphony?

[Jay Hamilton]

I'm having trouble placing the end and beginning of hairpins inside polyphony
I looked at the snippets found something but didn't really understand how what 
was there is different from what I've done.
here's a line of the work, notes and all are correct however the cresc should 
end in the middle of 3rd full measure and then a decres to the end
Thanks for looking this over.
Jay

\version "2.10.25"
\header {
  title = "Allemand a 4 (1603)"
   composer = "Melchior Franck"
    
}

upper = \relative c' {
\clef treble
\key c \major
\time 4/4
#(set-global-staff-size 25)
\override Staff.TimeSignature #' style = #' ()
\partial 4
<d g>4\p^\markup {"Allegretto"}
<g b>-.<g d'>-.\< a-. <g b>-.\><e g c>2<d g b>4\< <f a> 
<<{b8 cis d4-.\! d-.\> cis-.}\\{g4 a g e}>> <f d'>2\! r4 \bar ":|:"

}

lower = \relative c {
\clef bass
\key c \major
\time 4/4
\override Staff.TimeSignature #' style = #' ()
<g' b>4-.<g d'>-. <g b> <f d'> <g d'> c,2 g'4 <a c>
<<{d2 g,4 a }\\{g4 f e a }>> <d, a>2 r4
}

\score {
        \context PianoStaff
        <<
        \context Staff = upper \upper
        \context Staff = lower \lower
        >>
        \layout {ragged-right = #t }
        \midi { \tempo 4=42 }
}





Yours-
Jay

Jay Hamilton
www.soundand.com
206-328-7694