Zeiss scopes are easy to dismantle- if you know the way.
Best thing is to go step by step trough the zeiss discription for dismounting.
As by all zeiss models the most important point is the correct position from the elevation knob and lever for magnification ( or by zielvier and so on the lever for focussing.
Zielmultar is easy:
unscrew the ocular/eyepiece, take the corect position- focussing lever in the middle/elevation anti clockwise till stop, take up the saddle, on small screw holds the complete innertube. If there is no rust etc. in the inside you can pull out the innertube.
For reasembling you have to watch that the red points on the gears are matching.
Thats all for cleaning up and enough if it is mechanical ok.