On the drivers side below the brake master cylinder there is a gromet and existing wire loom. It is easier to see from the inside, you need to remove the knee bolster (lower dash trim) and pull back the carpet. Use something sharp (awl or coat hanger wire) and pierce along side the gromet, carefull not to nic any of the wires.
Theres also a location on the passenger side down low and is harder to get at.
ok i didnt mean the fire wall.. hehe im not that retarded.. i meant is there a hole that i can use for wiring... ok kewl driver side is perfect.. i wanna hook up a PA/Airhorn system in my car...police style...and i want it to look as best as possible! whats the best way to run wires once i have it in the gromet? up behind the cylinder and along the frame??