The aftermarket G-body headlight lenses those kits use are designed for filaments that run left-to-right. An HID arc runs front-to-back. The beam pattern is usually poor even though they're brighter & you also will not likely pass inspection becuase you won't have highbeams. IMHO you're better off getting the aftermarket lenses, but use H4 bulbs with stepped up wattage.
Tommy