btw, what year is your X?
Here's a write-up on accessing/installing fog lights on 05 X:
http://www.xterraownersclub.com/ubb/ultimatebb.php?ubb=get_topic;f=38;t=002848#000000
http://www.xterraownersclub.com/ubb/ultimatebb.php?ubb=get_topic;f=38;t=002850#000000
http://www.xterraownersclub.com/ubb/ultimatebb.php?ubb=get_topic;f=38;t=002851#000000