This is the rivalry thread, I am pretty sure you wanted the Misc GH Discussion thread for questions about setting up your GH3 PC. That being said, a great thread that answers most questions you would want to know about GH3 PC customs is here:
http://www.scorehero.com/forum/viewtopic.php?t=107520
If you have additional questions about the software of the game itself, try that forum.
As for how to make your Wii guitar work on GH3PC, that is a Hardware Forum question. Taken from the Controller wiki:
http://wiki.scorehero.com/ControllerCompatibility
"Wii Controllers
GUITAR HERO: Your PC must be equiped with Bluetooth. BlueSoleil∞ is a bluetooth device manager for PC. You also need GlovePIE to map the WiiMote bluetooth to a virtual joystick or keystrokes.
Tutorial∞ taken from the official Frets on Fire forums, detailing the process of using the Wii Les Paul on PC.
The ROCK BAND 2 dongles are all are recognized as USB game controllers."
Link for GlovePie: http://glovepie.org/glovepie.php
Link for BlueSoleil: http://www.bluesoleil.com/index.aspx
If those links and Forum suggestions don't help you, I am not sure what to tell you. Good luck, and have fun.
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