40 minutos - 2 horas
Earpiece speaker stopped working for no apparent reason about 6 months ago. Ended upgrading to the 4s and procrastinated fixing it.
Took about 60 minutes or so. The guide was awesome and the huge photos make it very easy to figure out if you're screwing something up. Once I got it installed I turned it back on and it worked straight away. Sold the phone the next day!
Be careful when adhering the earpiece speaker using the adhesive. I could tell that if I missed the right spot the connection wouldn't be made and the speaker wouldn't have worked.