It's more involved that you think.
The parts are easy to get. Expensive, but easy to find. The only real exception to this is the damn housings - they are available just about everywhere in the USA, but they've been banned in Canada, so I had to source them off fleabay, and most of the guys who are willing to sell to Canada charge out the ass for shipping.
The wiring is pretty simple too.
Making them fit is tough. You have to pull the headlight assembly, including the entire popup assembly, and pull it all apart. Cut the back off the metal bucket that normally holds the bulb - had to buy an angle grinder for this, the dremel was taking WAY too long. The rest of the assembly is some kind of composite material, and you have to cut away a lot more material to expand the room back there. Projectors are significantly longer and wider than the original bulbs. You'll also have to mod whatever bezels you decide to use, they don't fit nicely inside the 7x6 housings.
After you've made them fit, you need to make them water resistant. Especially if you live on the coast like me, where it rains well over half the year. Stock projectors are *not* water resistant, they are designed to be mounted inside of housings that take care of the waterproofing duties. The Infinity projectors that I am using have gaps where the high / low beam actuator mount, these are large enough that you could pour water in from the back using a garden hose, and the water would pour out just as fast. Personally, I bought a couple bowls that are the right diameter and depth, made from a composite that can take the heat, dremeled them out for the bulb mounts, and I'll attach them using waterproof high heat aluminum tape.
If you want lights that pop up lower than stock, you'll need to mod the arm and the mounting point for the arm. Be a good idea to mod the headlight plastic surround, too, so it looks like it was designed for the reduced height.
Starting to get the picture?