The side marker lens on the Mark I Audi TT (model years 2000-2006) is a simple part that clips into the side of the front fender. To replace this lens is really simple, but you won’t know that unless you know how to remove it. Since the side marker lens on my TT was cracked, I got a replacement part and wanted to write a quick little tutorial to help anyone who is looking to do the same job. If you need to change out a burnt out bulb, it will also require taking the lens cover off to replace the bulb.