Override django admin activity log

How can I override django admin main page in order to hide certain activities.

For example:

I don't want the admin to see which users he created on the admin main page.I'm thinking I could override the get_queryset method like this:

class ActiveLogManager(models.Manager):

    get_queryset():
        entries = LogEntry.objects.exclude(content_type=4, action_flag=1)
        return entries

But I don't know where to place the admin manager.