Making something that is in quotation marks possessive

I come across this problem a lot as a copy editor: If someone is making, for example, a song title possesive, where does the apostrophe-s go? I.e. "Here Comes the Sun"'s writer, or "Here Comes the Sun's" writer. I would think it should go inside the quotes, to make it look less messy, but I guess technically that wouldn't be accurate. Can't find a ruling in the AP stylebook. Thanks!