Hey can any body tell me where to find pictures of cylinder head casting marks on the net. I'm looking to rebuild a 350 4 bolt and have a few cores to choose from. I beleive them to be 1974 to 80. The two I'm not sure of are, a tall narrow tri angle shape, and a two step up shape. No double humps, Damn. I'm not looking for anything wild but would like to know what some of this stuff is without ripping it down.