Help! ...I cannot locate how to switch the default edit form of a sharepoint 2010 list to a new Nintex form for that list.

(Curiously enough, the Nintex form previously created on the same list in QA seems to be automatically designated as the default edit form. The same does not seem true in production.)

It seems a new Nintex form can be created OK in production - but it does not replace the current default Edit page (for that list in production). Is there a way to do this?