Replacing the Battery on an iPhone SE (1st generation) with an iFixit kit

 The fix worked. So - good. But it took a lot longer than I expected, and the directions weren't fantastic. I'd recommend that the directions and videos emphasize BEFOREHAND where the common problems occur. For me, this is remembering to remove and store the screws IN ORDER with a map. Most frustrating, however (and this is common for most iPhones) was removing the battery. The directions were terribly inadequate, and I'd bet fewer than 10% of fixers ever get the adhesive strips out. In this case I was left with no alternative but to dig the darn thing out with whatever tools I had on hand. It took AGES and I utterly destroyed the battery in the process of removing it. Needless to say, the risk of destroying the phone during this removal was very high.

Nobody's fault that I lost one of the six vital screws. Picked it up with a tweezers and it got squirted out of the grasp. These screws are TINY, and once they hit the floor, they're gone.

Particularly annoying for me was that the Philips-head screws that iFixit provided to replace the pentalobe ones each side of the lightning jack did not fit (too long), and I ended up having to reuse the pentalobes.