ON the sf and gt The oil pump gear has an arrow pointing to the crankshaft gear for alignment timing. I have an older model that does not have the mark on the crank gear. OK I understand that you put the oil pump gear at TDC and then the crank at TDC. Ok I have not split it yet. When turning the engine I see that the oil pump gear goes 180 to the bottom as the crank has rotated a full circle. When I split it will it make a difference? I mean if the crank was 180 degrees off would you be able to change the plug wires to compression or would it be 180 off?