accidentals in turns

I am using turns - in particular upper note first then lower, but the lower note needs an accidental on it. The convention in sheet music I have is that the accidental is placed below or above the turn sign, depending on which of the lower or upper notes are inflected. If I select the middle note of the turn and then click the accidental, it puts the accidental beside the note - which is not what I want. If I try to drag and drop the accidental to a point below or above the turn sign, it doesn't drop.