The What you need section mentions T4 and TR8 screwdrivers, but I don't see any mention of these in the instruction steps. Are they really needed?

Conversely, Step 12 requires a T8 screwdriver (not TR8), but this is not mentioned in the What you need section.

Can these be clarified?

Good guide - it took me about 25 minutes. At first the phone didn't appear to power up, so I thought I'd messed up somehow, but it came up fine after plugging into a charger.

Good stuff! Took me about 1.5 hours (replaced battery as well). This is not my first repair, but definitely the longest, most number of steps. Keeping track of all the different screws (and other little bits) is key.