I actually ran them through the interior. I'm in Utah and with our winters I didn't want my battery cable being under the car as I plow through snow
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It wasn't as bad as I thought. It forced me to do quite a bit of crap due to a shotty job connecting the new cable to the old one. I ended up replacing the starter thinking that was bad when really all I needed was a distribution box to connect the cables.
Running the wiring was easy for the most part. Start in the frunk and work your way back. There's a hole in the firewall on the top of the passenger's side firewall in the frunk. It'll take some motivation and elbow grease to get all the cable through it. It will eventually drop down under the glove box on the passenger's side. Pull it through and leave it all on the passenger's side foot well area. If you look up into the foot well you'll see a plastic air box, which sits about an inch away from the firewall on the inside. You should be able to see one of the bolts hold the air box in, run the cable above bolt against the firewall. This will put the cabling right behind (and down about 2-3 inches) from the stereo. Unbolt radio bezel and the center console. Run the cable all the way back under the console. Get behind the driver's side seat and pull out the clips holding the rear carpet on. You should be able to just pull it up and not out completely. You'll find a hole in the rear firewall around the engine lid pop, I can't remember if it's above or below it. This should put the cable in the engine bay right behind your fuse box. Connect the new cable to your old cable(s) and you should be good to go.