how do I run the amp power cable through the car from under the hood to the trunk?

for the wiring just find any wires that run through the firewall and see if you can pull it through. If you have a clutch try taking out the rubber cover and fitting it through there. If you dont have a clutch pop off or still a hole through where the clutch cylinder suppose to be. You can also follow the hood latch and try to fit it through. Use rubber gromets to make shure water doesnt go through. I would go strait to the battery terminal. the jumper terminals work too

I would normally ignore a comment like that, but what Tom is advocating for you to do is create a direct short with no Fuse Protection. Putting a non-fused wire through a hole with a moving metal rod will eventually wear through the wire insulation and short out directly to the metal ground. Please don't do that. Highly, Highly recommend that you find a proper rubber grommet, drill the proper size hole and seal up the opening. The wire, once inside the car can be run under the carpet near the hump with the other wires that go to the tail lights. If in doubt, find the wires that go to the tail lights and follow them back forward to find the route. It is also highly recommended that you protect that wire from shorts by using a fuse at the power source end. To save a hole through the firewall, see if there is a spare Fuse in the internal fuse block.

i agree with coach dan buy a wire kit comes with all the necessary grommets and instructions not hard but be very carefull drilling that hole