Honda BF35A-BF45A Outboard Motors Shop Manual., Page 459Get this manual
D-GPS INSTALLATION PRECAUTION NOTE: Carefully follow the installation instruction when install D-GPS1) Keep the D-GPS unit and antenna at least (10 ft) away from the outboard motor2) Be sure to connect the ground system to the boat
SPEEDOMETER TUBE INSTALLATION
1) Cut off the sensor nipple end at from the endConnect it the outboard motor tube and secure with the wire harness bandNIPPLE END
INSTALLATION Meters and other instruments should be installed on the dash boardIf any other location is selected, it will be necessary to use mounting plate with thickness of11 (0.040.44 in)NOTE: If the mounting plate thickness exceeds 11 (0.44 in), the bracket must be modified accordingly (hour meters up to thickness of can be installed)Tighten the mounting nuts evenly on both sidesOPENING SIZE
APPROX3 m