Would this work?

[Hellotalkie]

http://redoctane.com/universaladapter.html
I bought the original guitar hero for ps2 and just bought guitar hero 2 for xbox360. If I was to buy this adapter, would my ps2 guitar work with the 360? Just didn't want to give $60 for a 2nd guitar while I have a older version.

 

[Kirby64]

Doubtful. The Xbox 360 guitar has extra stuff the PS2 doesn't.

 

[Hellotalkie]

I mean sure I wont have teh dashboard button, but I am only using it for 2nd player, nothing really needed but the main buttons.