[Egg 3141592654]

If you are using the arcade drive, on the left of the arcade drive box, there should be 3 possible wire inputs. The top (you know this already) is where your drive reference (pink) goes. The next two wires below that are your axis inputs. I believe top is x and bottom is y (if not, right click the arcade drive box and click help. This outlines each input in more detail). To switch them, you only need to place the x axis in the other slot and move the y axis into the now empty slot you just moved x from. I was once there, so good luck with the programming!