Good that the ac is fixed. That timing chain noise, does it “click” faster as you rev up the engine? If it does, it’s most likely the plastic chain guide that broke and slip downward. You don’t have to take the whole engine out, although it will be a lot easier that way. The timing cover which is on the ‘front’ of the engine facing the passenger side wheel well has to be taken out. If I remember right the oil pan has to be taken down to take the timing cover off. That’s what makes it more complicated. Here’s a youtube clip on replacing the chain guide: https://www.youtube.com/watch?v=QI3xqgakdP0 and he has an update to it if you want to see more.