Its not that hard really, all you'll need is a dremel tool and cut a notch into the base so it fits a D2S housing like the 06 Coupe headlamps. But the way i see it, if you paid 600 whatever dollars for the housings, you might as well spend a lil more on some good quality bulbs.

 

the cutting part is easy. managing to get the black/brown strip without damaging the bulb is a bit challenging.