BMW E46 M3 - REAR 996 PORSCHE BREMBO CALIPER ADAPTERS BIG BRAKE UPGRADE - BR0020
E46 M3 Rear Porsche Brembo Brackets. The part numbers for the calipers are 996.352.421 and 996.352.422 these will allow for a E46 M3 328mm 20mm rear discs. Distance between caliper mounting holes is 130mm.