I am adding sport mirrors to 70 Cuda that had no passenger side mirror. LH side was not sport option either. I haven’t looked to see if LH holes line up ( mirrors shipped to body shop an hour away) but bigger question is placement of Passenger side. Do I just measure to LH side base and match? Or did mopar designers come up with another quirky moparism we all love and place RH side differently ( I do have the 70 correct mismatched mirrors).