I have rebuilded a "Davis Powerbeam I" once. Instead of the original 575 HID bulb I used a 100W car halogen bulb. After some math I get 1/20 of the original luminous. If the projector was rated to 300 ansi lumen it may be 10-15 now, incredible - isn't it =) But I placed the lamp as it was from the beginning and it was some way unefficient so I got plans to use a reflector instead. Ofcourse I wonder when my new bulb in my ASK A4 would die... cause the first exploded after 95 hour. I got a new but how long would this work. I got no warranties on this one because Infocus not longer produce it. Glad I get one new... They let me keep the old one so I been studing it for any attempts to be rebuilded. The HID-bulb is fixed with plaster so it would maybe be easy to refix a new bulb - if you even can get a HID-spare I doubt. But if I rebuild my projector for a 100W halogen It would give me 100 ansi lumen - can you really live with that? And the colourtemp is 2500-3500 kelvin for a halogen and 5500-6500 kelvin for a HID? Can you live with that to???