Firstly,
There is no horizontal adjustment.
If you need horizontal adjustment, your car is bent.
Dave
This is not true, these headlights are meant for electronic automatic adjustment in the European Fiesta, with that being said, there's no telling where the height is from the factory, most have found them to be level but myself and others had issues with them being uneven, or way low (@fST had this issue). The female hex that is right next to the high beam bulb boot is what is used for horizontal adjustment.
The EURO headlight assemblies are not designed for HIDs.
Use of any HID will cause some distortion of the beam.
While this is partly true, the correct bulb will prevent distortion, it's all about spacing and how secure the bulb is. With the bulbs I mentioned above, they can be tweaked to clear up the cutoff, almost like focusing a lens on a camera. I found the trick to be to manually bend the bulb mounting tabs to ensure it sits as flush and as tightly as possible, haven't had any issues. I may try playing with these metal rings to space the bulb out even further, which should match the backspacing of a traditional H7 bulb. It isn't even necessary, but I'm anal and want the best performance as possible out of these.
I have had issues getting these 100% perfect, but it's because I've had to go back and forth with adjustments, and it's taken several weeks of removing/reinstalling and driving at night, experimenting with bulb mounting and tweaking accordingly. If you want to make it easy and just stick with the brightest halogen bulbs, grab the Osram Rallye H7 bulbs, they are brighter than any "blue" tinted "xenon" bulb you will see on eBay and auto parts stores. They look good even compared to halogens, and cut through rain really well. They are more towards the 3700k color range though, so more yellow than 4300k HID bulbs which are more close to true white.
http://store.candlepower.com/osraulhiouh7.html
For those that don't want to deal with this, you could easily get the factory headlights retrofitted for roughly the cost of these European lights, but I love the LED DRL and it's a great conversation piece with other ST owners.