How to change Autorize.net text on payment page

[RadioFreq]

I am looking for a way to change the text that appears on the checkout page when you choose your checkout method. Mine currently has 2 options that I am using: Authorize.net and Paypal. I would like to change the text on this page to say "Credit Card Payment (Authorize.net)" so that the customers will now that this is the method to use to place credit card orders. I have searched through the .php pages and can not find the correct page that contains this text so that I can change it. Can someone please tell me which php page contains this text so that I can modify it? Thanks in advance eveyone!

 

Patrick Parks