So now I feel a little silly because I knew this was a newbie question to begin with. I used the tube and ear method and I'm pretty sure I isolated the ticking to the injectors. In fact, I didn't even need the tube because when I touched the fuel pressure regulator with my finger I can feel the ticking. It was a little disconcerting hearing that for the first time through the tube though, it sounds like something knocking which is kinda scary! I also put the tube on the valve cover and couldn't hear the ticking.

The part where I can feel the ticking is circled in green.

I'm still kinda curious why I never noticed this ticking before. I could of sworn it wasn't there before. Oh well, thanks guys.