I just installed a remote compass in the tail of my RV-4. The OAT and headset check are good but the heading is reading almost exactly 180 degrees out. I have not done the calibration yet because the aircraft is undergoing some major modifications and I can't run the engine right now. It just seems wrong that the heading would be off that much. I installed it with the connector forward and within 1 degree of the 10A. Just like the drawing. If I move a small magnet around the area of the module, the heading changes and then returns to the original heading when the compass is removed. Ideas?