Fig. 1195 shows the different type starter drive heads used on Ford cars. None of these parts are interchangeable and under no circumstances should they be confused or mixed.
The A-11381-C can be distinguished from the A-11381-DR and T-5019-2007, by the bore diameter. The A-11381-C has a 5/8“ bore, the other two heads have but 1⁄2″. The T-5019-2007 and the A-11381-DR heads can be distinguished by the difference in the thread length of the tapped screw hole. The tapped hole in the A-11381-DR is approximately 5/16” deep. In the T-5019-2007 it is approximately 3⁄8” deep. Check and segregate your stock.