abby normal

Any secrets to changing the serpentine belts on a 2002 Dodge Intrepid, 2.7L,
75k miles. They look like that could use a change since I've never done it
and I'm pretty sure they are the original ones.

Inside belt looks simple enough with the auto-tensioner. The outside one
looks like it needs to be tightened with a socket but to what tension do I
tighten it too?