TAKE THE DIST CAP OFF AND LOOK ALONG THE EDGE OF THE DIST YOU WILL SEE THE NUMBERS STAMPED THERE. IN LAST POST I FORGOT TO SAY TOP DEAD CENTER COMPRESION STROKE. BAR ENGINE OVER WITH BOLT ON THE BALANCER.TO SEE THE POINTER ON FRONT OF ENGINE I USE A SMALL MIRROR AND TROUBLE LIGHT , i HAVE A BORESCOPE NOW THAT MAKES IT A LOT EASIER. this will not get rid of po 340 , this code falure of signal from cam sensor, this can be caused from bad ignition wires, bad coil etc creating magnetic interference in area, check all those . use scan tool to clear code (after dist is put back in properly).