Gonna get my dart block after all. honing away on the right bank # 6 hole Whoaaa whats that little jagged streak yep crack right next to the head bolt hole.1/2 below the deck. I will sell the block and rotating assembly to a mud truck runner for cheap. What good are 4 bolt mains if you cant over bore it .030. Looking at Reher Morrison fully prepped block big m sportsman, not cheap. I will never build another engine on a factory block again.