The spindle (where the strut, lower ball joint, halfshaft, and outer tie rod end bolt onto).
I generally recommend removing the spindle entirely when replacing halfshafts so that you aren't bending them, as well as other components, at extreme angles fishing everything into place.
As far as turning the halfshaft ... meaning ... once it was attached to the spindle, you didn't spin the halfshaft (as when the tire is rotating), until everything was attached.