Hi there, looking to upgrade my brakes on my 05 A4 Ultra Sport with B5 S4 rotors and all. My brother used to own a 2000 A6 4.2 and when he sold the car he gave me a set of rotors and pads he was going to put on it but never did. I know the S4 rotors are 312x30 and so are the A6 4.2. Can I put the A6 rotors on my car, will they work? Looking at on the ECS website you get two different part numbers for each car.

Thanks!