Looking at getting the gt-r start button.... Lol
Amazon.com: GTR Red Start Button 2009 - 2012 - 25151-JF00A: Automotive
Product Description
R35 GT-R Ignition Start button switch unit. Perfect replacement if your start button ever gets stuck from coffee spills or soda. Can also be retrofitted onto 370z and G37. Simple plug and play makes for ease of installation.
DIY - Do it yourself guide is available at the370z.com as posted by "Triple's": Similar method can be done on the G37.