1964 C10 fleet side swb

[aggie91]

The difference between those measurements could be difference in the machining of the yoke and the end of the pinion shaft. Some times the pinion shaft could be deformed slightly if it is a old or used pinion. I always use the machined surface of the yoke to measure the angle. I use one level to set the yoke so that the cross shaft of the u-joint is level with the ground and them use the machined face of the yoke to measure the angle. Captain is correct on the indication of the arrow. It is the direction of rotation to get to zero or 90 (second photo showing 85.30)