While installing a 200A meterbase and tightening the 2"x 6" nipple, the KO came apart and (eccentric type KO's) so I made a call to the PoCo engineer and asked if I could use reducing washers as long as I bonded with a grounding-type locknut (the ones with the screw). He had no problem with having reducing washers but did not want any #4 copper in his meterbase.
What happens when the AHJ busts me for noncompliance with 250-94? Should I get an affidavit from the PoCo engineer?