It also depends on the brickies. We would layout out the boxes on the floor and provide him with a pile of pre-fab boxes with 36" straight stubs, a coupling on the end, and another pile of 36" nipples. He would set the boxes according to the mark indicated on the floor and when the courses got up to the coupling he would install the 36" nipple and continue so we were never holding them up. We would have a guy randomly following the brickies around to ensure that everything was correct. For the top nipple which had an elbow we would have a guy work with them to cut it to length and ensure that the elbow was facing the proper direction.