Hi, it may well have been posted before, but I can't seem to find it. What other Audi calipers are a direct replacement for a b5 s4 1998 ? Have heard that any b7 chassis audi running 321mm discs will mount straight up but looking for some clarification on this. On another note, what are the best pads to run on the standard calipers ? the brakes are pants LOL.