The iFixit guide was b---s---, they froze the phone for no clear reason, and destroyed the entire phone. I almost gave up on buying because of them. Here is a tutorial by fixEZ. All you need is a heat gun (I used a hairdryer) and a playing card.

https://www.youtube.com/watch?v=BCKxAQXdTJ8

It is tough but I've opened up a couple to replace a broken display. They are difficult to put back together well, but it's doable.