Does anybody know how to run 4 guage power wire from the battery to the trunk in a 97 geo prizm? Or at least how to get it through the firewall?

2 things you can do , find where the main wiring harness comes through the firewall and see if there is enough room to slide the wire through that hole or get you a drill and make a new one , just check the other side and make sure you are not drilling into anything else