I just got my kit in the mail today, but I have no idea where to start!
I read the DIY and it looks like it involves removing the bumper in order to mount the ballast and taking out the actual head light case. Is there a way to install the HIDs without removing the whole bumper and casing?

 

Jack up car and turn wheel to the side. Then go through the fender liner. You can see the bulb from there. I believe one side has windshield wiper bottle in the way. I took my bumper and headlights all the time to try different type of h4 hid kits. I think it's better to remove bumper and headlight

 

Are we talking about GD (2007/2008) or GE (2009-current)?

GDs were very hard on bulb replacement, requiring access through the wheel liner.

GEs, do NOT require access through the wheel liner for the bulb. there's more than enough room to take out/insert a bulb from the top.

If you have the Sport trim, you can probably mount the ballast by removing the fog lamps (1 screw per lamp is all that holds it in). OR, take off the grille cover and then take off the upper grille (though, I think that's kinda tricky)... and reach down.

 

If its a GD3. Take the time to just remove the bumper and headlight to make the job easier and have a clean install.