SMD disk specifications

[shadoooo]

Hello,
well maybe my memory has blank spots.
I have two CDC Lark Disk modules I would like to revive, they are in good
shape, but only one has a cartridge included, and they are not identical.
Not sure if the other one could be employed without cartridge.
I never found a manual with exact model correspondence, I found years ago a
manual for very similar drives.
IIRC there was a sort of adapter board between SMD and (xxx blank spot)
interface. There was a description of the interface, it was really similar
to SMD, but wasn't SMD...
Maybe I should check again the Lark model number.

Andrea