The 98's theft system is a ***** that is integrated into the computer. I have heard of some folks being able to turn it "off" via an aftermarket chip, but most companies don't like to do it and from what I hear, can lead to other problems.
Try contacting
www.JMSchip.com by phone.
But if you are TRULY having theft system problems, its probably computer replacement time....
I would contact your local Ford Techs and see what they have to say.
Did you get your codes pulled?
__________________
Uncle Sam
"What the hell is up with all the gauges?
Calling Captain Kirk, your ride awaits... Phasers on stun...."