Category Listing on Sites Listing Page

We am using a modified Blog Type plugin to add categories to my wordpress instance. We have added a listing on the Sites listing page (as we thought that was the best place for large sites like mine so it wasn't too big).

wp-admin/network/sites.php

Attached is a screenshot of that page.

We have some other cool things on this too that allow me to email users with a certain category. We also have a report page that gives me an overview of how many are in each of the categories.

Anyway, the problem we are having. What we would like to do is have a filter dropdown on the above sites page that will let me only display a certain category (so we can get all the uncategorized stuff and go through and set categories if the client's dont set their own category). This would be like the drop down filters on the posts page (wp-admin/edit.php).

Thanks for any advice how we might do that without editing the core. :slight_smile: