I think you’re mixing things up here. It seems like you’re trying to measure the time difference between channels, but you’re focusing on overhang. The time difference between channels is more closely related to azimuth than overhang. If you perfectly set the overhang on an SME V, the maximum error would be around 1.8 degrees. However, the measurements you’re discussing are more related to phase and azimuth. Of course, all adjustments are interrelated, and remember that high distortion can be caused by many factors beyond alignment.