How do you take the serpentine belt off a vortec 4200 engine

There is a belt tension-er that is round & has a 5/8 is bolt on it.(It may have a metric bolt but it seems like this size usually works)Anyway u turn this bolt counterclockwise & u r turning against a spring in it & it loosens the belt & u can remove it.Under the hood there is usually a diagram that shows u how to re- thread the new belt back on,otherwise u will have to be sure to pay attention to how it came off,or draw yourself a picture of how it was originally installed.Then loosen tension-er again reinstall belt,and ur done.