The door's been installed, and the 2x4 in the opening is covered by the metal door frame 1 3/4 inches. There is a light switch near the door which tells me that there is another stud but it's at least another inch out if not on the other side of the switch. Assuming that the trim (2 inches wide) is to be installed 1/4 inch from the door, I will have to nail it through the metal into the stud beneath it.