I have a 34 Unsingle and a 34/32 Unsingle combo. I tried to set both up identically (comb, butte and barrel marks) and even though i was was very detailed in my measirements and settings -- i got different sight pictures and POIs.
After spending some time setting them to get the same sight picture/window, i patterned them (using the same LF choke) to get the same POI. To no surprise, both barrels are at different marks (3, 5), and one comb is 1/8 high while the other is 1/4" high. ...for the barrel adjustment I count clicks not marks.
Long way to say tha each SG is unique as is each fit is to the same person -- so the barrel mark settings will vary between SGs even with the same manufacturer and model.