I screwed this into the #1 cylinder in place of the spark plug. I had already removed the rest of the plugs so the engine would spin easily. Then I slowly turned the crankshaft pulley counterclockwise to roughly 20 deg after TDC and screwed in the piston stop until it contacted the piston.
I marked the balancer at the pointer with a piece of tape. Then I turned the engine in the other direction (clockwise) until it hit the stop again at about 20 deg before TDC and marked the balancer with a second piece of tape.
Now I could remove the piston stop and turn the crankshaft until the pointer was halfway between the two pieces of tape. The was now my true TDC. You can see the pointer is off by about 1.5 degrees so I needed to move it over. I only had to elongated one of the two holes on the pointer to put it in the correct position.
