[Plugin: Pinterest "Pin It" Button] Change Pin It image?

Would like to change the Pin It Image to the red button like here:

http://theadventurebite.com/wp-content/uploads/2012/04/pinit.gif

I know it must be simple to do but everything I am replacing is having no effect.

Thanks!

http://wordpress.org/extend/plugins/pinterest-pin-it-button/