The first change ended up stopping the entire site from working. I know I used the single quote, so not sure what that’s about.
As to the second option, I tried putting it in a few places and each time, it made my entire back-end stop working. The site was still there, but it wasn’t showing the new read more text and when I tried to navigate in wordpress, it would give me an error saying it couldn’t be accessed. So, either I was putting it in the wrong spot or there’s something else causing problems.