For a recent customer service data project, I needed several GD::Graphs and simply duplicated my call to individual code for each graph:

print "<img src=http://www.url.com/cgi/custsvcgr.pl>";
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#!/usr/bin/perl -w


use GD::Graph::bars;
...get data here...

my $mygraph = GD::Graph::bars->new( 600, 350 );

$mygraph->set( dclrs => [qw(green pink blue cyan)] );
$mygraph->set(
    x_label => 'Section',
    y_label => 'Satisfaction',
    title   => 'Customer Service By Question',
    bar_spacing => '5',
  )
  or warn $mygraph->error;

my $myimage = $mygraph->plot( \@graph )->png;
print "Content-type: image/png\n\n";
print $myimage;
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I think you will find other examples similiar to this one with a super search.