My client's Siri and dictation was not working. I figured that the front facing microphone was no longer working.
It was pretty easy and it went well. the hardest part is keeping the ambient light sensor and the proximity sensor in place while you put the speaker in, then holding all that in place while you put the bracket on top.
Make sure to have the right tools and stay organized. I recommend the magnetic project mat and the iSclack to make the project even easier.