PN 630-1057 and PN 630-1039 Both appeared to be identical just packaged differently. It was a tight fit in the intake and I had to run a 1/2" drill down throuh it to get the valve it but it was quick and easy. Rock Auto also list a "help" part # which is where NAPA cross referenced to these #s The breather is just an off the shelf crome Edlebrock with a rubber grommet that fit perfectly..
