Posts: 1,162
Threads: 26
Joined: Aug 2005
I've never tried to clean one without fully dismantling it. I guess I had a misspend childhood (:-)), I rebuilt my first ASR33 while still at school without the manuals (and that thing has over 1000 parts), so taking a disk drive apart doesn't bother me. If you follow the article you'll not upset the head alignment (don't remove the stepper motor or track 0 sensor), so you don't need the alignment stuff.
As regards getting inside a 9121. Unplug all the cables from the back, then either push the power switch in (as if to turn it on), or pull the button off. Then remove the 2 screws from the back, and lift the back edge of the plastic cover up. It'll 'hinge' on the bottom front of the bezel and will then come off. Note how the tabs hook over the front of the metal chassis.
There's a plastic cable guide post in the middle of the chassis, held on by one screw. Take that out next. Then remove the 3 screws holding each drive in place, lift the drives out and unplug the cables.