Thanks DeltaDave and Stevebfl. I purchased a 19mm box end wrench and cut it in half with a hacksaw. There is not a great deal of space down there! I loosened the nut with a socket and long extension first. Then held it with my shortened 19mm boxend as I turned the allen hex screw counter-clockwise. I adjusted slowly and then test drove the car. After adjusting 3-4 times, it is now fixed! Hmmmmm....I don't think the dealer adjusted the box at all! Maybe he didn't have a special home-made 19mm box-end wrench!
[This message has been edited by Webmaster (edited 03-14-2000).]