I need to find a hole in my firewall somewhere near the glovebox about an inch across to run gauge sensor wires through...the car is a 93 touring

 

You can open up the main wiring harness grommet -- it's right below the glovebox.

 

I had the same problem last weekend installing my boost controller. Tried for two hours to get through the seal and wire loom you are talking about. What a pain. I was worried about nicking a wire and getting water into the loom by cutting the boot. Eventually ended up drilling a hole through the firewall that came out directly in front of the ecu. Much easier, and I was able to see that the wires/hose was not crimped. Put everything in with a grommet and sealed with some silicone. Makes for a clean install, and it's all hidden behind the fender liner!

 

rotoober, if its not too much trouble can you snap a few pics of where it passes through, so i dont **** this up

 

Already put it back together, but let me see what I can do tonight when I get home. Make sure you get the right size grommet for the number/size of wire, and the right size drill for the grommet.

 

well I went a little big on the grommet so that when I get my next 3 gauges i wont have to bother with more drilling, just have to poke out the silicon ill use to plug up the open space.

 

ok, here it it. Remove the wheel, all the clips/screws on the fender liner up to the spring. Carefully pull the liner out(it has a wacky interior piece that lines up with the fender vent) of the way a prop it up on the brake caliper. Remove the interior kick panel. I put a shop light in the car by the ecu so I could see when I drilled through the firewall. I put my hole about 1 1/2 inched down for the flat perch the fender liner attached to and about 1 inch in from the threaded bolt coming out from the firewall(also used this to tiewrap the wires/tubing down). I believe it used a 10mm nut. When you drill through into the interior, all the insulation-stringey stuff will bind up on the drill. I pulled the drill out and pushed the stuff away from my hole with a small screwdriver and drilled thru the rubber mat. You should now be able to see into the passenger area. Run your wires thru the same big gromet in the fender that the other wire loom goes thru by the brake lines in the engine compartment. I found that this worked great for my boost controller hose wires, nothing is exposed and it is all protected from you friends big feet by the kick panel. There is also plenty of ground points to hook up to in the area.
Hope this helps.