When I ran mine ( 4 gauge) I looked at the firewall just above and to the left of the Brake pedal (from the inside) and their was a hole, but it was only on the inside. I drilled it thru and made it a tiny bit bigger, and got a snug fit for 4 gauge.
2000 CSVT #1172 of 2150 Toreador Red...Birthday -> 1/4/2000 *Indiglo Gauges *Drop in K&N *Sylvania SilverStar Highs in Lows *Fog light Fix *Pioneer Premier P730 *Sound by Audiobahn *White HVAC Panel *Security via Ungo MS2007 *Elky Mesh Mod