The ADA entrance is just south of the press box. They have golf cart style vehicles that most people use. I'm pretty sure they have shuttles from the ADA parking lots to this spot.
They also usually have about 10 students (working in pairs) that can push people throughout the stadium in wheel chairs, there usually isn't much demand for this service, they will also come back after the game and pick up the people. The students don't get paid, but they get money donated to their charity (for years it was Project Haiti). I know they have been having some issues the last few years getting students