18. Using a permanent marker or dye, I marked the top of the valve and installed the intake and exhaust push rods on one cylinder. Notice the top of the valve has the paint removed from the center and toward the right side of the valve tip. When I hand spun the engine over with the pushrod and rocker installed, the top of the rocker took off the paint where it was moving. This indicates that the top of the rocker is not centered on the top of the valve. I used a Comp Cams adjustable pushrod (part number 7905-1) and repeated the steps. The correct pushrod length was determined to be (part number 7809-16) 7.266 inches long.