how to edit signup page, can't find text in wp-signup.php

Hi, i have already edited some text for page, but for the life of me i can't remember how!

I have even done a grep of whole site and search the DB for the custom text, but cannot find which file, i thought it would have been wp-signup.php, but the text is not in there?

I wish to edit the custom text i have already entered, plus this text

(Leave fields blank for a random password to be generated.)

would also like to set the default option in signup page from

interested in Pro site

to

Not Now

thanks