2000 ls V6 ticking

Hello, I just noticed today that my car has a slight tick coming from the engine. I have not had much time to look into it and was just hoping someone may have a idea about what it may be. The engine has 212000 miles on it. It has been very good to me. I have never worked on a overhead cam motor. Could this be a lifter, or would it be a rod. Plugs were just changed so I dont think its spark knock. Thank to anyone that can help.

whens the last time you had the timing belt changed...this can actually give you whats mistaken for a ticking sound alsowater pump