distributor intermeadiate shaft?

A piston stop is screwed into the #1 spark plug hole and adjusted to stop the piston. When the engine is rotated CW by hand it will stop the engine from turning when the piston is near the top. You mark the damper and then rotate the engine in the opposite direction CCW and mark the damper again. Half way in between the marks on the damper is zero or TDC. Summit and Jegs sell piston stops. Be sure the engine is on #1 compression stroke when you perform this test.
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