This took several months from initial phone calls to the final installation, but it paid off when everything ended up working the way it was intended and I learned a lot about pneumatics in the process.
The idea was to have solar panels stored beneath other solar panels that could be deployed on slides when the vehicle is parked. Since the bus has an onboard air system for the brakes, wipers, door-opener, etc, it was a worthwhile step to deploy the panels with air cylinders.
The extra large panels, 310W apiece, measuring 990 x 1640mm (39" x 65") required the use of some very pricey outdoor-rated drawer slides. I recommend if you're considering a similar project, use narrower panels so that you can use more readily available components.