The first step in accessing the firewall is removing the passenger side front tire.
The second step is removing the plastic splash guard inside the fenderwell.
Now you have complete access to the factory firewall.
There is a small nipple in the firewall that can cut off and the hole can be used to run the power wire from the battery.
I purchased a power distribution kit from like Wal-Mart. I installed the in-line fuse close to the battery post, and then ran the power wire under the center console where I placed the distribution block.
