WAIT WAIT WAIT!!!
Don´t bother trying to get through the firewall! I ran 2x4guage cable on the underside of the car with the brakelines back to the trunk and got inside it through the 2 big water drain plastic plugs. I ran the cable inside a plastic protective pipe (like these pipes that cover the engine harness). I have tightened it with cable clips and it´s working very good. With huge cable diameters there´s no other way to get into the trunk, because you´d still have to get through the interieur when getting through the firewall.
So run the cable from the battery down below the brake fluid reservoir to the brake lines undersides. Follow the until getting over the rear axis and enter the trunk via the drain plugs and you´ll be fine.
P.S. Mine is a sedan too.
Don´t bother trying to get through the firewall! I ran 2x4guage cable on the underside of the car with the brakelines back to the trunk and got inside it through the 2 big water drain plastic plugs. I ran the cable inside a plastic protective pipe (like these pipes that cover the engine harness). I have tightened it with cable clips and it´s working very good. With huge cable diameters there´s no other way to get into the trunk, because you´d still have to get through the interieur when getting through the firewall.
So run the cable from the battery down below the brake fluid reservoir to the brake lines undersides. Follow the until getting over the rear axis and enter the trunk via the drain plugs and you´ll be fine.
P.S. Mine is a sedan too.
