Ideally you want to remove the light units from the car, as all the instructions below will be more easily done.
If you unplug the power from the side of the ballast unit underneath the light unit, the plug is only 12 volts and has two terminals. Take the back cover off the light unit, and unplug the ignitor from the HID bulb. Unclip and take the bulb out.
Make up 2 wires with spade connectors that go from each terminal of the plug to each leg of a halogen bulb. You'll find splitting in half a spade connector will fit into the terminals. Crimp the metal frame around the bulb to make it wider, so that it'll wedge against the hole in the lamp - the metal clamp to hold the bulb in the lamp should then fit over it and hold it in place.
You'll not be able to put the cover back on securely because you'll have the wires trailing out the back of the lamp, but this should get you through the test.
Refitting the HIDs is the reversal of removal. :lol: