As a rule, the disconnect has to be put in the room with the elevator machine. Some states require the disconnect to be 18" from the strike side of the door. There is also a requirement that there is a square from the front of the disco that is 30" wide and 42" deep. If it faces other electrical equipment then it must be 48" deep.
Incase you want to know, I am a Draftsman for a Elevator Company. My job is to draw the plans to install the elevator and equipment in the building. These are all Building specific.