Realize that more may be damaged than just the keyboard. The keyboard is integrated to the top case, which is good news because it's a fairly straight forward DIY repair. Just follow the guide. Do purchase the recommended tools, ' every job is easier when you use the proper tools.

BTW everymac indicates the cases are not that different so a 2011 topcase should work on your 2012 machine. To verify I would contact iFixit Customer Service before ordering.

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