Chev 350 Vortec Engines Rocker Cover Adaptors To Fit Early Style Rocker Covers 551542Valve Cover Adapters, Aluminum, Small Block Chevy, V8, Kit Valve Cover Mounting Style: Perimeter bolt Spacer Thickness (in.): 0. 375 in. Spacer Material: Billet aluminum Spacer Finish: Natural Bolts Studs Included: Yes Gaskets Included: No Quantity: Sold as a kit. Notes: Adapts small block Chevy 1955 86 perimeter bolt valve covers to later 1987 2002 small block Chevy center bolt style cylinder heads. Requires the use of RTV sealer on the head side of