Is it generally the case that if my trim tab controller has no LED indicator of position then the sensor is not installed to relay tab position to the helm? My 2007 DA has just the switch controls. I have read the threads about the kit that can be installed to either relay to a new dash controller with indicator or hook it into NMEA for the VesselView indicator. I'm not clear if the sensors that relay tab position were something that just starting coming standard on the trim tabs at a certain point/year such that they might be on my boat and I just need to install a new controller/indicator. Thanks.