how to hook up gauges

I am trying to hook up the following gauges, any help would be appreciated.

Fuel gauge and rpm's

1. This is how I think the fuel gauge should be hooked up.

from pos. battery to electronic fuel sensor, from fuel sensor to gauge then from gauge to neg on battery. Is this right?

2. what do I need to do to wire my tach to my motor.

I have a 1988 or 89 u.s. marine force motor 125hp. "please no dissing the motor have heard it all already", I have the motor on a 87 bay liner trophy series fish and ski boat.

Thank you

Re: how to hook up gauges

1. backwards but it would still work (I think). Positive from "I" terminal of ignition switch to one terminal of the gauge. Other terminal of gauge goes back to tank sender unit. Sender unit will either be grounded to tank or will have a separate groung that goes to battery negative. The "I" terminal only has power when the ignition switch is on so you don't drain the battery.

2. Same "I" terminal to +12 volt or positive terminal on tach. Ground terminal to any ground under the dash or black wire in the engine cable. Purple wire to signal terminal on tach. Again, the gauge will only have power while the switch is on. The tachometer may or may not read zero and may read the last RPM when the engine was shut down. USUALLY, but not always, the tach will zero if the switch is turned on without the engine running.

Re: how to hook up gauges

thank you so much

zell66

Re: how to hook up gauges

ok went and looked at my ignition switch and I don't have an "I". I have a 'A', 'B', 'C', 'S', AND 2 'M''s, so what do i do now??