The only gauges you really need working is the fuel. Oil temp and volt/amm can be taken care of tastefully with a triple gauge set as in the pic. That's what we did. Left factory gauges in for looks. Our cars messy, but you get the idea.
Myself, I would rather have all of the factory gauges working correctly, especially with it being a ralley set up and a console car. I just don't care for under dash gauges especially with a nice interior like yours.
