it's not really rocket science.
Pop front and back floor panels.. or kick panels? whatever those plastic side things are called.
Then there is a large one between the doors, take that one off.
Then there is the fuse/kick panel, take that off - there is a screw though, be careful to not break it.
Fold your back seat - please don't ask how to do that. There has been a millions threads on that.
Run a 2 or 4 gauge through the hole in the firewall, under inside fuse panel, inside the door seals, wedge it under the back seat, through the trunk bracing, button everything up and there you go.
Also, be careful to not cut yourself on that trunk bracing - that stuff is dangerous. I was bleeding for awhile. heh