If anyone did things in the same order I did; you may run into the same problem with the driver installation. Because I had already set up my machine and didn't attempt the triple display set up right away. When I went to install the nvidia driver it told me, "Unsupported System: This computer will not support GeForce or Quadro Mac OS X edition cards." I knew right away it was because the drivers were for Mac Pro but not Mac Mini which I had made my hackintosh into for compatibility with thunderbolt. Here is the fix without having to re-run multibeast:
Drag "304.00.05f02 Web Release.mpkg" to the desktop and let it copy. After it is finished right click on it and choose "Show Package Contents". Open the "Contents" folder and open the file "Distribution.dist" in TextEdit or better yet TextWrangler.
Change the line that says: var system_models = ["MacPro3,1", "MacPro4,1", "MacPro5,1"];
to: var system_models = ["Macmini6,1", "MacPro3,1", "MacPro4,1", "MacPro5,1"];
(Or whatever your system is in place of "Macmini6,1)
Save the file and attempt to install the nvidia driver package from the one on your desktop that you just modified. I followed my own steps just like this and was able to activate my third display without re-running multibeast or changing to a MacPro5,1 (Even temporarily).