So the way they want it is the od of the bottom cylinder is the datum feature. Not the groove or top od. The axis of only that cylinder is datum a. They do not want the whole axis of the part as it will not be concentric.
So the way they want it is the od of the bottom cylinder is the datum feature. Not the groove or top od. The axis of only that cylinder is datum a. They do not want the whole axis of the part as it will not be concentric.