How to interface GPS to Yamaha speedometer

[jercat]

Gentlemen,
I have the Yamaha Fuel Management Meter (FMM) for two Yamahas 225 FStroke. I need to know how to use the part number 6Y5-85721-F0-00. It is my understanding that I have to cut the W (white) wire that comes from the Yam Speedometer to the FMM and connect it to the signal lead that comes from the NMEA connection on the GPS. I will use a Scotchlok connector to connect both ends.

The questions are:
1- Is the above procedure correct? Cut and connect W to W?
2- I see two additional cables (R,B) on the square plug coming from the Yamaha speedometer. Shall I continue using them with the W input coming from the GPS?
3- Shall I eliminate the W wire that comes from the Yam Speedometer or keep it?

Your advice will be greatly appreciated as usual. joseeruiz@libertypr.net

[boats.net]

Here is the diagram
FMM GPS Connection.JPG

[jercat]

Thanks for the diagram. Excuse my ignorance, but I need to know if the "signal lead for the speedometer" is elliminated? The diagram only shows one coupler B and two signal lead. Do I completely unplug the speedometer lead?
Thanks again

[boats.net]

Yes you can use one speed signal source either the speedo or the GPS NMEA 0183 output.

[jercat]

Thanks, for your prompt reply and patience.

[jercat]

Moderator, one more question to you. When I connect the GPS to input speed into the Fuel Management Gauge (FMG), will I get the GPS speed on the Speedometer?

Will the FMG feed (input) the speed from the GPS to the speedometer gauge?
Your help is greatly appreciated as always.