Randy, the winding motor circuit on the 120 Volt AC IBM weight driven master clock is no more complex than a simple desk lamp circuit.
The circuit begins with the plug at the end of the cord and ends at the motor but half way to the motor the cord splits with one wire connected directly to the motor, the other wire splits off, terminating at the fan gear switch normally open connection. The other screw terminal on the fan gear switch is the operating contact of the switch. A wire from the operating contact on the fan gear switch then connects to the other connection of the winding motor.
As said earlier, a photo of the interior of the clock would be helpful. Some small AC electric motors are simple two wire, others have both a field and armature windings (4 wires) which may have either internal or external terminations.
The fan gear actual switch is mechanically a toggle switch, not momentary; it has two states....on and off. It is operated mechanically from the fan gear. Make sure you understand how the weight winding drum operates the fan gear and that you are familiar with the lock-out device which prevents the weights from falling when the clock movement is removed from the case.
I can understand your concern about spoiling the motor as they are no longer available new and scarce if used but Randy, these motors have a nameplate describing their character. Along with your photos, include a word-by-word description of the motor name plate.