Yea.... only cut you will need to do is one for the grommet in the headlight back cover plate. I just fitted a 35w 8000k HID kit on my leon and it looks mint!!!!
 
I paid about £50 for my kit. works a treat.. looks mint. Yes you will need H7R bulbs which have a little black out strip to reduce glare. The H7 bulbs are for the projector lens type.
 
Do I have to test where the negative and positive pins are on my car before connection or is it soo easy a baby could do it

Nerayan
 
You can test them yea, but if you get it back to front the light error code will flag up on your dash and you just swap it over :) if I remember... the O/S headlight the top was positive and it was the other way around on the N/S