Frankiemigs

What’s up guys. So I’m looking to upgrade my front seats in my B8 A4. I found a pair of S5 black leathers that I am digging. Hopefully can pick up if the price is right. Few questions If anyone can help. Are they a direct swap? Like seat rails, and wire harnesses or do I need to swap harnesses and rails? I also read that I need to swap the rails if I get the S5 seats so I can attach the seat belt on bottom which is fine. More worried about wire harness and lights on the dash. I don’t have Vagcom so I wouldn’t be able to clear any codes. Any info would be greatly appreciated. And if anyone knows anybody selling S4/S5 seats or even sport seats in the central jersey area that be great. Thanks.