Installing a DEFI boost gauge. Using fuse taps to tap into fuse panel on inside of car, driver side footwell.

Black (ground) = Going to put this under the bolt that's holding in the hood latch release bracket.
Orange (12v switched) = ?
Red (12v constant) = ?
White (illumination) = ?

Also, with the fuse tap, do I only need to put in one fuse or do I need to put in two fuses? The fuse taps have two fuse slots.

Edit: Another question, I also noticed today when looking at the fuses, that some fuse amperages dont match up with what the table shows it should have. For example, the 'RADIO' shows a 20A, but the one that's in that slot is a 7.5A. I quadruple checked to make sure I was looking at the correct slot. Counted from both ends, it's the correct slot, but fuse amp is different. There are other ones like this too. Big deal or no? Never had an issue with anything electrical either.
Any help is much appreciated.

 

Orange (12v switched) = I use ACC #32
Red (12v constant) = I use a lead from the battery.
White (illumination) = I tapped into the VSA button so when the park/dash lights come on my air gauges dim.

Also running slightly higher fuses are not a that much of a big deal. Running below recommended is a problem tho.

 

The add a fuse has 2 slots. 1 for the original fuse and 1 for the new fuse that has the wire tap coming out.
why is there a constant for this gauge? does it store information? there should be power, ground and illumination.
i grounded my wired gps to the metal bracket running under the steering.

 

It's a Defi Red Racer gauge. I'm not sure if it stores anything. Thanks for the replies!