IBM 3270 Maintenance Manual page 570

6. Install the two mounting screws. Move the
diskette drive in or out for a clearance of 1.0
mm (0.040 inch.) between the rear of the front
panel and the face plate; tighten the screws.
--
(SIde View)
7. Remove the terminating resistor only on drive
B (5-602-25).
8. Install the cover of the system unit (5-100-3).
9. Connect all cables.
October 1984 5-602-9