Default Item Order is by ID - what file do you need to update to make the default order based on Date or Title?

Anyone ever make this update to sort by a different column by default? I'm guessing a change needs to be made in one of these files?

 

/administrator/components/com_k2/views/items

  - view.html.php

/administrator/components/com_k2/views/items/views

  - default.php

  - element.php

 

 

Any thoughts or suggestions?