IIRC they are not all the same, but i think if you get one that says 2.0i if a cosworth one isn't listed then it'll be fine, sure that's what i got(twice) now. I think the main difference is the sender hole in the top of the tank varies in size. There's alot of chat about the swirl pot design in the tank etc but i thing thats all taken too seriously. The only think you have to watch out for is some of the aftermarket tanks have plastic swirlpots and some people have had the tanks powder coated and melted the bit inside, but i wouldn't worry about that if i were you, the tank is painted already. Also do't forget to fit a new fuel tank strap SHOULD still be available from Ford and not too expensive. Under £20 i think.