I have a 03 Accord EX sedan. I just finished running a power cable through the Accord's firewall. On the 03 Accord sedan there is a hole in the firewall about in the middle of the firewall at the location right behind the centre AC/Stereo stack. It has a rubber grommet in the hole, which in my car was pushed into the hole from the inside of the car. I remember trying to pull this grommet out through this hole, but instead it fell inside someplace, so I had to purchase and new grommet. Rest was easy. I pushed my 10 guage cable through the hole, and could see it just behind the stack. (The hold is fairly large... about 3/4")