You'll need to follow this IFIXIT guide: [guide|10775|MacBook Pro 15" Unibody Mid 2012 Upper Case Replacement]. Once you get to this point you'll need to pull the screws or pop rivets off the back side of the shell to remove the keyboard. If you have rivets you'll need to replace the broken ones.
As to the keyboard many come with spare rivets and you'll need to make sure you got the correct one. The other option here is just replace the upper case which is a lot easier.
You'll need to follow this IFIXIT guide: [guide|10775|MacBook Pro 15" Unibody Mid 2012 Upper Case Replacement]. Once you get to this point you'll need to pull the screws or pop rivets off the back side of the shell to remove the keyboard. If you have rivets you'll need to replace the broken ones.
As to the keyboard many come with spare rivets and you'll need to make sure you got the correct one. The other option here is just replace the upper case which is a lot easier.
You'll need to follow this IFIXIT guide: [guide|10775|MacBook Pro 15" Unibody Mid 2012 Upper Case Replacement]. Once you get to this point you'll need to pull the screws or pop rivets off the back side of the shell to remove the keyboard. If you have rivets you'll need to replace the broken ones.
As to the keyboard many come with spare rivets and you'll need to make sure you got the correct one. The other option here is just replace the upper case which is a lot easier.