install on a 2000 expedition

You need a bypass module for the PATS system. There are keyless bypasses we sell and also key required bypasses as well. The keyless versions are more expensive but you don't have to worry about a spare key in the car being found.

As for a spare key being found.. here's something we do at my shop.

With the customers approval of course, we will cut the key from the head from the key, put it in the dash and return the metal to the customer.. gives him/her a little more piece of mind, knowing that a functioning key is NOT in his car!