Clutch arm position alone isn't the most accurate way of determining proper setup as it's a bit inconsistent & ya really need only insure there's no slack in the cable but no real tension when the lever is released.
The clutch actuator arm is on a splined shaft, but it's not always pressed on in the same position from engine to engine - in fact I remove mine and turn it in a spline or two to help prevent it catching on my pant leg *shrug*