Sam Jewell: The following concept sketches pertain to the service tunnel ride. Please review this storyboard prior to reviewing these concept sketches.

The Service Tunnel Ride

The RailCar Pulley System

After exiting the service elevator the spies will enter an old mine car (the pulleys will be out of sight). Hopefully the service elevator will be at the same height as the rail car, so we will not need ramps for wheelchairs here.
They will have to close the door (maybe to touch some electrical contacts together and release the brakes) and then they will be able to propel the car along the tunnel by heaving on the rope.

The rail car will in fact stay still! We will however give them the impression that its moving by bumping them around on the hydraulic jacks (the wheels are only touching the ground when the spies enter and exit - they cannot rotate).

The rope will have some resistance applied to it, so that it can be made hard to pull for any number of spies. It will also drive the ceiling past at the same rate as itself (see next sketch) to reinforce the feeling of movement.

The related storyboards can be found at the storyboard main page.