I didn't want to upgrade my iPhone 5 at this time, so I wanted to try fixing it
The repair went fine. The only tricky part was removing the old battery. There was a lot of very sticky glue holding it in. With patience, the glue finally let go. The ifixit video was extremely helpful. I watched the video on another device and followed it step by step, pausing and repeating sections if I want not sure how to proceed.
Take your time, prepare a clean well lit work surface and don't get distracted. The screws are super tiny, so work on a surface like a towel or cloth so they won't roll away.