What is industry standard in measuring a tray? If they are working the opposite, tell Ford HO that too. As for the sensors, which ones? The reverse sensors, or for side impact or something? I'm surprised there is an issue with them at all. They aren't usually callibrated with any data, they work completely on sonar and as far as I'm aware, shouldn't reference any vehicle size at all. Are the located on the tray, of under it, with the tray hanging over the top? Give the dealer another call in regard to the wire. If they don't want to help, just say thank you, and you will discuss it with Ford Australia direct.