You might as well get both the upper and lower ball joints, as one has to come out to get the other out. I don't remember the exact sequence, (remove lower then upper or remove upper then lower) and I just recently did one side of my truck :7:, but they go back in the reverse order. If the upper is worn, you can bet the lower is also and needs to be replaced.
[on edit]Here's a how-to article that I think is more in depth than the one SuperDutyTrooper posted (and it's on our site - but unfortunately buried a bit deep). Ball Joint Installation It says the lower has to come out first then the upper. The press screw needs to extend thru the hole for the lower to remove/install the upper.
It was easy thanks for the help. It just sucks that as as I droped the jack I stepped of the driveway and tour the ligaments in my right ankle. So it will be a while before I am wrenching on the truck other than putting on the tow mirrors tonight once the wife and kids go to bed.