How do you change the fuel filter on a 2004 trailblazer?

i have the replacement filter but is there some type of pressure switch to press to shut off the pressure from the pump?How do you change the fuel filter on a 2004 trailblazer?
there is a pressure port in the fuel rail. it looks like a tire valve and has a plastic cap on it. push the center to release the pressure but stay back or you'll get a face full.How do you change the fuel filter on a 2004 trailblazer?
the easiest way to remove the fuel pressure from the fuel line is to simply remove the fuse that goes to the fuel pump and then start vehicle, it will run for a few seconds then go dead, there still may be some fuel in line, it just wont be under any pressure.