2005 Accord LX 4 door 4 cylinder

I'm trying to feed a wire from engine compartment into the cabin. I know there is an unused gromet on the firewall right at the middle of the center line, sort of right side of the heater core water line, and from what I hear, it is for this very purpose. (to install third party accessories)

What I worries me is that from inside, I can not tell what is right behind this gromet. There is no visibilities from any angle.... I don't want to start poking hole on this gromet and start feeding wires, only to snag or puncture something inside.

Does anyone have any time of documentation or experience in using this gromet?

I need to feed wire directly from under the hood. Two 12 guage wires.