I have a few questions about the autometer gauges. I am looking to install 2 2 1/16 autometer gauges in my new gauge overlay bezel and im trying to get a vacuum gauge but can only find the boost/vacuum gauge. This does the same thing right? Also have any of you installed the Water Temp. gauge, Oil Temp. or Oil Pressure gauges? How hard is it to install them and what kind of things need to be done? The instructions arent the greatest on the autometer website