BBC Black Powdercoated Steel Top Mount Compressor and Alternator Bracket. Compressor bracket is designed to mount a Sanden 508 compressor on the passenger side and alternator bracket is designed to mount GM alternator on the driver's side on a big block Chevy with a short water pump. These brackets mount to the water pump and to the top bolt in the head. Brackets are laser cut 1/4" steel and then powdercoated for a durable long lasting finish. They measure about 12" tall from the top water pump mounting bolt so you should double check hood clearance.