its not hard. Most people just pull the sending unit that is up by the filter that drives the dashes gauge. Your stock gauge will not register anymore but the new one will show an exact temp. If you want both you can use some brass fittings to make a T to hold both but its tight on space.
Put a boost gauge there. With supporting mods Like RichV said, it's not the best place, but you could Tee off where the pressure is obtained, down by the filter. Install an extension hose and Tee it off. Personally, I would not recommend disabling the oil pressure gauge, even if you have the stock one. Oil pressure is very important to the life of the engine, and you'll want to know if you are losing pressure.
Consider filling the pod with a coolant temp sensor, if you don't already have one. You'll get a lot better resolution than the stock one.
Yea I have the Saleen style pod on the dash with oil pres. And water temp. I was wanting to get the pod around the factory gauges with the two extra gauge pod holes and puting air/fuel and oil temp or maybe intake temp rather than air/fuel ratio.