Just get an aftermarket HID kit. The non-HID kit from Ford was still ridiculously expensive, like over $400 if I remember correctly. And I don't believe there was any computer module included either. I know of one car I worked on that had one HID and one halogen, and I sold the guy a used HID bulb out of a car I was parting out, and all I did was unplug his halogen and plug in the HID and everything worked fine.
-91 Cougar LS, coming soon, complete overhaul with a 427" Windsor.
-90 XR7 5-speed black on black w/sunroof, MP2, coated rotors, double intercooler, 15%OD, ported heads, comp stage 1 cam, 85mm TB, 90MM LMAF, 80# injectors, and ported big valve heads
-98 Mark VIII LSC, Procharger P600b, TR3650 swap and 3.73s.
-90 SC Automatic rustbucket winter beater
-97 Tbird Sport 4.6 Nice weather daily driver
-"Your buddy Mike is INSANE!" -ClintD's dad