http://mywebpages.comcast.net/syclone1/hid/page1.htm for instructions. I think i did one thing differently though. When you drill holes through the housing to mount the projector i used a 1/8th drill bit, then pounded the screw a little bit into the hole, then screwed it in so it kind of made threading in the plastic housing. Then i put a nut on the other side all the way down to the body and Jbwelded it.

I did this so the screw had something for leverage to turn. How you adjust these is you turn the wingnut and it will push or pull the screw which is has a spring on it so you can adjust it
The first time i did it, i just drilled a hole and pushed the screw through, did it all up to find out when i turned the screw it would just keep turning in the same place, not moving. It's also very hard to make sure the projector is lined up straight so i tested it 2 different times and redrilled the mounting holes. Make sure everything is how you want it before you seal it back up
If i did this again, i would try to get see_fuu to build me a pair, but that's a tad bit more expensive. Luckily i had a bought black housing headlights, and i did this project with my oem's. this project spanned over 3 months, partly because i was lazy but a lot of time waiting for the jbweld to dry.
You can look on ebay for parts, i got my set (projector/bulbs/ballasts) from a member named heydanchan on ebay for $450. One of the bulbs wasn't working so he upgraded from some osrams to phillips 85123 which are better.
You can use pretty much any projector, but keep in mind the smaller the better. If you get really big ones you will hvae to relocate parts