I've got a '97 AWD 5.0L. I have a Chilton manual, but it didn't tell me that I had to go in thru the wheel wells to get at the plugs! Not sure how accessible your plugs are on your X, but if similar to the '97 then:
Jack up the front, secure on stands, remove the front wheels, remove the mud skirts, and using a combination of socket extensions, remove and replace your plugs. When removing the mud skirts, be careful not to tear the material or break the clips. Grasp each expansion clip while holding the material firmly and pull it straight out. It takes a pretty solid tug to get each clip out. Don't be timid. Don't worry if you break a clip...you can buy new ones at your favorite auto parts store. Torn skirt, however, is not a good thing.