Ticking sound from engine

https://youtu.be/-dVu_AecayI
you could take out the alternator and spin it to see if it make noise

 

I'll try it out. Seems a bit congested in there, but I'll try pulling It out tomorrow and testing it out. Will update.

 

UPDATE:
So after I changed the tensioner, as I said it kept ticking. Over the weekend I was gonna pull out the alternator but due to how complex it was I decided to give autozone a try to see if they can at least semi test it while in the truck still.

As I began to drive it over, about a 5 minute trip...the sound vanished! It's been gone all day, kept intermittently starting it to see if it came back and nothing. Could the tensioner have needed a "break in"?

I know I gotta swap out my water pump, in the process of ordering it online, but I'm optimistic that it just needed to run a bit.