Need help with wiring

When I do a trunk mounted battery I use welder's cable. It's MUCH less likely to have issues over a long life than std battery cable or the cheap kits. Also, you can either solder the terminals or use Moroso terminals that screw together and make a great connection without heat. All other connections should be soldered. I run the negative from battery to the lower side of the frame rail, then a complete 2nd cable from the frame rail spot where the battery cable ends up to the front of the car to the block. I also run a seperate ground strap to the firewall off the block. I run a 10ga wire from the output stud of the alternator directly back to the cut-off switch, and then from the switch to the battery positive. This assures that when the alternator is charging, there is a low-resistance path back to the battery but the switch will still cut the power. For the positive cable, I run it from the cut off switch to a positive buss bar under the hood, and then to the starter and fender relay. Then you can use the buss bar for any connections like fan relays, fuel pump relays, head lamp relays, etc. That limits the length of wire for every circuit, and it will work for years.