remove the driveshaft, and take it to your big vise.
find a socket to fit inside where the cup goes, and squeeze lightly to remove the spring clip
remove from vise, and remove the spring clip
find a larger socket than the cup, but smaller than the driveshaft, place small socket on one side, large on the other, then squeeze it out with the vise, you may need a pipe for leverage. it will go crack twice, then it will shove the cap into the socket
place 1 cup in the drive shaft, turn the new joint in, make sure to face all u joints in the same direction, or they will bind. place 2nd cap on, and squeeze carefully with the vise, until the caps are flush with the outside
squeeze the cap in with the socket until you can see the slot where the spring clip goes, on both sides.
install new spring clips
install grease fitting
bolt it back in the truck, use blue loctite on the nuts to keep them from backing off.
[IMG]http://i620.photobucket.com/albums/tt282/dustybumpers
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good luck, as you see, not a hard job, just take your time