Here's a quick how-to for wiring up GReddy 52mm gauges using the clock wiring harness. I'm not sure if these instructions can be used for the 60mm GReddy gauges as they have peak/hold features and may include additional wiring steps. I'm sure these instructions can be adapted for use with other brands of gauges but I installed GReddy gauges so that's what I'm limiting my information to.

Basically the benefit of wiring the gauges in this manner will provide for a less permanent installation and allow for quick and simple removal and re-install. Also, it eliminates the hassle and clutter of vampire taps.

This deals only with wiring the gauges, not with installing the sensors or routing the wiring. Info for that can be found elsewhere in ScoobyMods.

Tools & Parts:
wire stripper/crimper
(optional) soldering iron & solder
4 U-shaped spade connectors

Steps:

As always when doing electrical work, make sure the battery is disconnected before proceeding.

1) strip about 1/4" to 1/3" of wire sheath off the end of each wire on each gauge

2) match the wires from each gauge up by color (black, red, orange, and white) and twist the wires of all 3 gauges together, the tighter the better so they won't unwind on you

3) (optional step) I used a soldering iron and soldered each set of twisted wires

http://www.buckfutter.net/images/cars/my_cars/02_wrx/parts/640x480/04.jpg
As you can see my soldering skills are not the best, this was my first time ever soldering so you don't need to be a pro to get the job done. Just get some spare 18awg wire and practice a few times.

4) using a U-shaped spade connector, slide each set of twisted wires into the connector and crimp the connector to keep the wires in the connector (optional - I soldered the top of the wire to the connector itself to ensure that it can't be pulled loose)

I can't tell you exactly what size of spade connector to use, I just grabbed one and plugged it into the clock harness (after the battery was disconnected of course) and it fit snug so that's the only fitment suggestion I can offer.

5) trim off one side of the "U" so that only one prong is left

6) wrap each connector in electrical tape - I wrapped mine a lot and in the picture below it may seem overkill but I felt it necessary because you won't be able to get each connector in the harness all the way and was nervous about them possibly making contact due to vibration - sort of a "better safe than sorry" mentality on my part

http://www.buckfutter.net/images/cars/my_cars/02_wrx/parts/640x480/03.jpg
Like I said... overkill on the electrical tape

7) get the gauges where you want them to be and then plug actual harness plug into the back of each gauge

8) plug each connector into the actual clock harness as snug as possible - the plug on the actual clock housing that you remove from the dash is labelled with which wire is for what, using that label I matched up the connectors that I made with each slot in the clock harness
BAT = Red wires (constant power)
ACC = Orange wires (switched power)
LIG = White wires (illumination)
GND = Black wires (ground)

I apologize I can't tell you what the corresponding colors are on the clock harness that the GReddy wire harness match to. Its very easy to look at the label on the back of the clock and match up which ones plug into which slot on the clock harness though, thats how I did it.

http://www.buckfutter.net/images/cars/my_cars/02_wrx/parts/640x480/07.jpg


Sorry the pictures are crappy and there aren't more, the batteries were low so I tried to avoid using the camera.

And the obligatory "all done" shot...
http://www.buckfutter.net/images/cars/my_cars/02_wrx/parts/640x480/02.jpg

Speaking of "obligatory" I guess I need to add the obligatory caveat that I'm not responsible if you mess up and that this may void your warranty, do this mod at your own risk; etc., etc.