I'm going to install oil, fuel and boost gauges in my 04 WRX wagon and was wondering if anyone had any suggestions before I begin. For example, a good location for the wiring, tubing, etc.
I will be putting them on the windshield pillar.

 

they will move this to INTERIOR, exterior, ...

 

well theres a small grommet under the brake or clutch. you can wire it through there, but just to be sure not to push the grommet all the way through.
theres alots of grommets to choose from, just look in your firewall.

 

For the wiring, tapping into the clock harness worked well for me. There is ground, switched 12V, and accessory 12V. Just yank the clock up and the wires are right there.

 

Do you want them on the pillar or the dash?
Do you know what type of gauge (manufacturer) you'll use?
Do you know what size gauges you want?

That will help you make a decission.

 

I'm using Autometer Ultralite gauges...I'm mounting them on the A-pillar. They are 2' 16". Fuel, oil and boost.

 

If you're using the pillar, once you start taking the car apart you will find all kinds of room to begin your routing.

Like scoobyboy said go through that grommet near the clutch, it is the easiest way to get to the engine compartment.

Just make sure that you tie everything off neatly, you don't want to release the clutch and pull a tube out.

Are you going to install an egt gauge?

 

no, not right now. Not doing any tuning.

 

are you talking about the wiring to light up the gauges?