Well I finally got to the front gallery plugs. By pure luck I had the correct conical one in place! We are replacing the dist. gear damaged Crane roller cam with an Isky roller cam. Had to stop working last night when I discovered the Isky cam is threaded for a smaller 3/8 standard thread bolt to hold the timing sprocket/fuel pump concentric while the Crane had a 7/16 fine thread bolt. Will the larger 7/16 hole in the fuel pump concentric be a problem with the 3/8 bolt, or will I need to get one with the 3/8 hole , if available ?