2004 300 HPDI wiring

In reading through the rigging guide for my motors I came across what I thought would be very useful. I can wire in a NMEA cable to Yamaha part #6Y5-85721-F0 which then plugs into the fuel management meter. The NEMA would plug into my Furuno NavNet VX2 electronics which in turn should give me better fuel mileage numbers. I have spoken to several shops around town to see if this would really work and all I have gotten are shoulder shrugs and "I don't know." Now the part only cost $50 so that is not a problem - smoking either the FMM or the NavNet would be. So has anyone worked on this problem?

You are correct as far as the Yamaha meter working with input from your gps. You won't have to unplug your pitot tube anymore either to keep the mpg functioning. I don't see anything being fried. How many hours on your 300?

Thanks for the reply - it was the answer that I was looking for. The tach's show 750 and +-800 hours but a while ago I had the mechanic hook them up to the computer it showed that the motors had some where around 350 and 400 hours. I am hoping that I will get plenty of use out of them before I have to pony up and repower.