Here are some tips I've learned while doing the install:
Time: 2.5 hrs for a beginner like me.

These are the materials/ Tools I used:

Phillips Screwdriver
Wire Cutters
Needle Nose plyers
Scissors
Very small flathead screwdriver
1 inline fuse holder ($2.50)
1 250 7.5A fuse (6A or 8A can probably be used) ($3.00 pack of 5)
fuse size = 1/4" x 1 1/4"
1 Standard size female tab connector .250 width
1 Butt connector ($2.00/pk of 10)

Assemble the gauges and wire fuses first and test your wiring before trying to take anything apart from the car.

Cut the inline fuse wire in the middle, one end goes to the positive wire from the gauges, connect together with the butt connector.

The other goes into the femal connector. Put your fuse in the holder, mine had a spring the hold the fuse in place inside the holder.

Here is how the wiring goes:
Gauge (+)---butt_conn---inlinefuse_fuse_holder----f_conn

Once you get the wiring done, connect the female conn to the back of the fuse panel (plug #3, T - Same as used for Shock Sensor - This gets power when the headlights are on.)

Gauge (-) black wire to the screw at the top of the fuse panel on the front side.

Turn on you headlights and gauges should now have power. Play with the switch, holding down the black button lights the numbers more or less.