[dcb]

yah it is a pretty simple task for the code. I think arduino is a good fit for this, lots of examples of displaying values on an lcd and the microcontroller has several analog ports. The hardware interface is pretty simple too if taken one port at a time.

1. Oil pressure: might need aftermarket sensor and a tee, but divide it to a 5v peak signal.
2. Oil temperature: same as temp
3. Voltage: use voltage divider (can use internal resistor in processor as part of divider)
4. Amps: use shunt and op-amp, or use hall effect sensor.
5. Outside temperature: thermistor as part of voltage divider

Each of these will look like an analog signal to the arduino (basically an atmega) and the basic arduino comes with six analog ports.

setup:
init lcd and analog ports

loop:
read pressure on pressure analog port
update pressure on lcd
read oil temp on temp analog port
update temp on lcd
...