I'd be very surprised if Jim at Lynxmotion could not provide this
In any case, from a quick read of the page, it looks like the LS-540S is
for just the the motor; you'll want the mounting specs for the gearhead
that is attached to the motor. Most of these types of gearheads are face
mounted using three or four screws in the face (shaft end). They should
be able to provide the mounting centers, the thread type (probably 2/56
or 4/40, or metric, and the maximum threading depth.
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