I would suggest you not completely disassemble the focus block. You can remove the face plate as well as remove the focus block from the stand to clean the internal gears.
-First remove the stage and condenser holder from the focus block. Also remove the objective turret.
-Then you will need to remove the top plate by unscrewing the two screws circled in blue.
-Then you can move the face plate up and off by turning the coarse focus knob.
-This will expose the six bolt holes/bolts behind the face plate (the top two are circled in red). You will need a long slender screw driver to reach deep into the bolt holes.
-Unscrew the six bolts and the focus block comes off the stand. Now you can access some of the internal gears for cleaning.
Zeiss Focus Block3.jpg [ 40.49 KiB | Viewed 464 times ]