Another user asked about how to remove and install the headlights on the 2. Here is a written description. I'll take some pics soon that correspond with the write-up here.
Here is how to remove and install the headlights, SUPER easy. I have done a similar thing on a few cars, and I think these are the quickest and easiest I have ever done. It just takes some patience.
First: Remove two 8mm bolts that are holding your splash guard on in the wheel well. You'll need to remove the one that is about a quarter inch in from where the bumper cover meets the fender. You'll also need to remove the one that is underneath the bumper cover, behind the pseudo-splitter right there near the edge of the wheel well. This is the same one you would remove to change your foglight bulbs. Then you need to remove one of those plastic pop-fastener style screws. The one you need to remove is near the top of the wheel well, in about an inch from the edge of the fender. Do this for both sides of the car.
Next: Open your hood. There are two relatively large black push-tab screws that hold the bumper in place. They are on either side of the giant Mazda logo near the hood latch. Those can be popped out easily be gently lifting with a flat-blade screwdriver. Next, remove the tiny screws that are on the top of the bumper cover close to the headlights. Now your bumper cover can be easily pulled back while working, making it possible to pull it out far enough to slide your headlights in. The last thing you should do here is remove the large top-facing screws that hold the headlight in place. There are a total of four that hold it in place, but only three are visible from the engine bay. Two of them are back near the rear of the headlight. One has a 10mm bolt head on it, and the one right behind it has a philips-style screw head on it, and it is similar to the other pop tab fasteners throughout the car, except that it is a sheet metal type screw. You'll also have another 10mm bolt headed screw that holds the headlight on right in-between two of the tiny bumper cover screws slightly inboard from the blinker area, on top of the bumper cover. You can't miss it.
Next: Once you've removed those, you can reach down with your hand and grab the bumper cover near the fender on the splash guard side and gently pull it straight out. It will pop off. Tuck the splash guard in under the bumper cover edge. The bumper cover is held in place by about 5 or 6 tabs that snap into the fender from behind. Once you get this loose, I would recommend putting some blue painters tape along the edge so you don't scratch your paint while working, or when you put it back in place later. The last bolt you will need to remove is underneath the headlight, on the outboard side. It faces directly out towards the side of the car, and it is right underneath where the bumper cover meets the fender. Just slightly forward from there. You'll need a ratchet to reach it, something that makes an L shape. Remove that bolt, and now your headlight will be completely free. It slides forward towards the front of the car to remove. It has a long spindle that helps it mount in the right place, so be careful to pull straight forward. You'll need to really pull the bumper cover forward to get this last bit to work, but it's so flexible that it's really pretty easy.
After that point, you can unhook the stock harness from the back of the headlight, mount it to your new headlight, and follow the directions in reverse!!