you may want to do some weight analysis.... I think the 460 is almost 30,000lbs base boat..add the gear most +40's have aboard and you may be up against the 30,000lb limit of the linear drive...so you may want to go to the next higher capacity drive.
On my 42' there was a plate attached to the rudder post, beneath the steering quadrant and a similar plate for the drive attached to the structure beneath the aft berth for the drive itself..this was hydraulic, as space for the linear was not there, short or long. Rudder position transducer was mounted above the quadrant. This was an Autohelm st8000, I believe