I'm planning on hooking up my power inverter to my battery. I don't really feel like drilling and I also plan on adding 4 guage wire for amps down the line. Is there any exsisting hole in the firewall that can fit 2 8/10 guage wires and a 4 gauge?

 

There is a small cut out on the rubber just above and to the left of the brake pedal, this is the perfect location to run the cable as it is on the same side as the battery. You will still have to drill a hole to get the wire through.