The archive post you reference basically says to go into SST (or DST from manual IPL if not doing concurrent) and tell the system you want to remove a disk. It should have a value for how long to wait, then it flashes the light on the drive. You remove the failing disk. Then you go back in and tell it you want to add a disk, from a very similar screen. Stage the disk in the slot but do not fully insert prior to selecting the add option. Then when it flashes, you put the new disk in.
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