Ive read many different threads and I havnt been out to actually look at the car's lights yet. Why do you have to drill holes in lamp casing for the wires. A simple explanation will do its just not clicking for me at the moment. Thanks

 

The stock housings have a plug port on them. You can't really run aftermarket HID wires through this. Most people drill a hole in the center of the access cap that clips on and run the wires straight through.

You can see the port on the left and other access cap that you'd drill through on the right in this pic.
The HID kit should come with a boot to go over the wiring where it goes through the drilled hole. You'd also want seal the wires where they go through the drilled hole with rubber cement or silicone to keep moisture out. The boot will make it look clean, but won't keep moisture out.

 

It's what you have to do with hid's. You can leave the back of the headlight housing open, but you'll get water in there (bad) when you wash the car. Unless you can fit the ballast and all the wires inside the back of the housing, you need to make a hole.

 

I mounted my ballasts on the bottom of the headlights and they fit perfectly. This may not be the case for all HID kits, though.

 

The best spot I found to place the ballasts are behind the PS fluid reservoir and behind the airbox. They tuck in nice and tight and no mounting is required.

 

You can get the slim kit and fit the tiny ballast inside of the housings.

 

Thanks guys the picture is what I really needed. Ive seen some people drill a hole on the bottom of the headlights where they mounted the ballasts. Good or bad idea?

 

Mine hole is drilled right in the back where is says "valeo" I didn't do it the person b4 me did. havent had ne issues with it.

 

Spend the extra money and get the ultra slim 55w ddmtuning ballasts. $45 and if you have the headlights that have the cut out on the bottom you can literally mount the ballast in the headlight where they would from factory. My Valeo e-codes did not have this spot however.

DDM now offers a 35w ultra slim full digital ballast with igniter built in. This one may be able to fit in any headlight. It's also cheaper at $35

 

do I need a relay harness if I buy the DDM's? I already bought a set of Notto's from car id but after all I hear about the DDM's Im about to send those back.