Hello knowledgeable monks

I am seeking your wisdom on how to insert lines into a specific place in a stanza.

The stanza is as follows:

<stanza 12.34.56.78>
    sl1  this is my line
    sl2  justanotherline
</stanza>
[download]

I would like to insert the code either after sl2 or just before the closing stanza tag. Either way is usable, whichever is simpler. (There could be more stanza lines after sl2. This is just an example.)

The code that I am using to locate the stanza that I want to change is as follows:

while (@array){
        open ("VN", ">", "$array[0].tmp");
        open(my $config, "<", $array[0]);
        my @change = <$config>;
                for (my $i=0; $i<=$#change; $i++){
                        if ($change[$i] =~ /\b$ip\b/){
                        $change[$i + 1] = $nc ."\n";
}
[download]

Thank you for your wisdom in this matter

j