IBM RT User's Setup Manual page 236

6. Pull the wire latch aside, place the diskette drive on the rails,
and slide it into drive position B. Ens ure t h a t the wire latches
hold the drive firmly in place.
7. Look at the diagram of the disk and diskette cable bundle,
which is already installed. The first two (if two are installed)
fixed-disk drives and the diskette drive in position A connect to
this cable bundle.
Section 2. Removing and Installing Drives in IBM 6150
AJ ZIF099
To Diskette Drives
In Positions A and B
AJZIF100
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