Reading and interpreting the measurement of existing sensors

Hi all, I'm new to this forum so please excuse me if I'm posting in the wrong place etc...
I'm designing a smart system for my dad's yacht based around an rpi server which at the moment is just a media server and NSA sever.
The next phase of my plan is to use arduinos (possibly the pro minis? ) and to create a wireless sensor network for the boat diagnostics. First sensors being water level and fuel level. As we already have sensors for these, using varying voltage to display the tank levels on the dials, i was thinking that I could measure the resistance and or voltage of the wires from the sensor and work out the fill level.
The sketch to do so wouldn't be hard as I am quite able at programming, especially python which the pi is build around, and as the sensor is linear all I should have to do is fill the tanks, measure the voltage and divide by 100 to get the value of 1% fill level.
I just would like to know if I'm going the right way about doing this, if you have any suggestions on what kit to use and if anybody else has done this (I'm sure they must have!)

Regards,
Sam McCracken (15)

Sammythehacker:
... and as the sensor is linear all I should have to do is fill the tanks, measure the voltage and divide by 100 to get the value of 1% fill level.

Is the sensor really linear?

Can you give us a link to the sensor used and also the indicators?

For the system to be truly linear you probably need to have a nice cuboid shaped tank.
Aren't the tanks on yachts usually weird complex shapes to make best use of the space available?

Have you already looked at the NMEA2k standard for instrumentation on boats?

It's a layer on top of CAN bus so susceptible to signal breaks, but you could wire it point to point for reliability.
For a small boat Ethernet would also work.
Wireless just adds extra unreliability.