#!/usr/bin/perl
use strict;
use vars qw($myexitvalue);
use MyLastEnd;
use Foo;
use Bar;
use SomeOtherModule;
use MyFirstEnd;

# rest of script

#MyLastEnd.pm
END {
     $? = $myexitvalue;
}

#MyFirstEnd.pm
END {
    $myexitvalue = $?;
}