Your going to want it right in front of you and in an easy to reach spot, because your going to be playing with it constantly and you want to be able to see the warning leds if you set that up.
I like that, but it has 2 gauge openings. I only plan on one gauge. But that is certainly an option.
Just use the one if you have to, don't worry about anyone giving you **** for leaving the other empty, once you get a scan gauge there is no point in having multiple guages for minimal mods...