The A2 on the controller is for plug braking which EZGO doesn't use anymore (it never worked right). The newer stock and aftermarket EZGO controllers don't have a A2 on the controller. If the controller has 2 cables connected to A2 you can remove them from the controller and bolt them together or make a new cable. If the controller only has 1 cable on A2 just eliminate the cable completely, the other end of the cable would need to be removed from the F&R switch. Your best bet is to leave the A2 empty and wire the cart like the diagram here. Everything else on the diagram here should be the same. The cart will run fine without any cable connected to A2.
Here's a EZGO Wiring Diagram with A2 on the controller for plug braking.