I don't live there so not much help to you, however I recently replaced the screen on a 4S for my niece. She bought the kit from Amazon and got me to do it. It's a damn fiddly job, as you can imagine, the screws are extremely tiny, and you have to be very careful prising up the computer ribbons. I watched a step by step video on YouTube first then followed along with that. A table top or head worn magnifying glass is a MUST. It took me about two hours to do it so I can understand why some retail places charge £50-£60 for doing it. Good luck in your quest.
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