Sure!  It won’t break the install.  To change the Amazon account do the following:

  1. From the Amazon home screen, go to Settings
  2. Click the circle right until you see My Account, then click the center circle.
  3. Click Amazon Account.
  4. Click Deregister.  Give it a few seconds to deregister.
  5. The next screen will either let you use your existing amazon account (Register) or create a new amazon account (Create an account)

Below is a video we created on how to do this: