I have a 16 ft Bluewater that has mis-matched speedometer and tachometer gauges. The tachometer is connected and working fine, the speedometer has never been hooked up. The speedometer I currently have requires a pick up mounted on the transom. I would like to skip that and get a gps speedometer instead. At the minimum I want to replace the current speedometer with a gps unit but I am open to getting a new tachometer as well to have a matching set. I have no idea what brand marine gauges are any good. Any recommendations are appreciated.