1: There screws that attach to the headlights are adjustable too, so you should be able to screw them in and out (or up and down) as you need to...Like the plastic screw on the bottom of the picture.
(The bolt that's circled red attached to one like it too...There's 4 per headlight...well, 5 but you don't use one when you install the DEPOs)
Here's the other side of that headlight...you can't really see it, but the circled bolt is attached to one...
2: The adjuster is towards the back, it looks like you can use an allen key to adjust it, but you can use a screwdriver I believe...
In this picture, if you look at where the wire is coming from, it's that hole in the middle
If you look at the back, you should see gears that turn right below it.
3: I just let my HIDs hang haha...There's a few places that people mount them at...A popular place that people put em at is the bumper support...A metal piece that's hidden under the headlight, behind the bumper.
Hopefully I made some kind of sense and helped you out somehow!!
-Randy