Sorting the signature list by date ascending

Thanks for a great plugin!
I am trying to get the list of signatures sorted by date ascending rather than the default descending order.
I found some information in this 1-year old threat:
http://wordpress.org/support/topic/plugin-speakup-email-petitions-change-sort-on-signatures-to-chronological-order

So in class.signature.php, I changed line #75 from
ORDER BY $db_signatures.id DESC $sql_limit
to
ORDER BY $db_signatures.id ASC $sql_limit

The list is now correctly reordered except for the signature numbers which are still in descending order.
Any suggestions? Many Thanks.

https://wordpress.org/plugins/speakup-email-petitions/