How do you change the PCV valve on a 2002 Ford Expedition 4.6 liter?

The PCV is a small black or grey plastic item, which is fitted down into a rubber grommet in the passenger's side valve cover. It will have a large diameter vacuum line attached to it. Replacing it is simple. Pull it out the valve cover, remove it from the line, and install the new one. It's a 1 minute job.