it is that easy. refer to step #1.

power will come from a switched source in the fuse box - usually an empty fuse slot. ground will come from grounding the gauge to the chassis. lighting of the gauge will come from tapping into a dash light - usually the cigarette lighter illumination light, or another shource that turns on with the vehicle lights, but does not overload the fuse...

this is really not that hard of an endeavour...