The bolt is "shouldered"... You should buy a correct replacement... still available from GM.
It is a special bolt. The shank diameter is also smaller to allow oil to pass. Buy the proper one. I don't have a picture of the actual bolt but this picture shows the oil flow past the bolt.
-- Edited by jc on Monday 21st of May 2012 11:01:34 AM
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'68 Parisienne 2+2 Convertible Matador Red (Resale Red but not for sale).