Im sorry, I dont want to be a dick, Merry Christmas btw
Using an existing hole would be the BEST/EASIEST way to run a wire. less drilling in your car, the better.
MAX Watts means jackshit. Look at RMS
8 AWG wire would be fine HONESTLY. You really dont need 4 AWG till your pushing well over 1000 watt RMS.
4 AWG is bigger than 8 AWG, thats why they measure it in GAUGE
Inline "crappy" MAXI / AGU fuses work just fine, depending on your application. For his needs, those would be fine. ANL is a larger, more expensive fuse. To be honest, a fuse is a fuse.
Using the wrong Wattage Fuse is what the problem is. Lets say my system. Over 1K watts RMS and I decide on a 10 amp Maxi Fuse. Yes, It will pop/melt.
A lot of myths in car audio.