I will tell how I set mine up, first my battery is mounted in the spare tire well from there I have 2/0 fine strand welding cable going to the cut off switch which I mounted on the deck near the passenger side.
The rest of my cables are 1/0 welding cable including the starter cable, the first one leaves the cut off switch and goes up to the remote solenoid which I have mounted on the heater case, I have 2 more 1/0 cables coming off the power side of the solenoid one goes in the passenger side kick panel to a power post and the other to the front of the car mounted to the core support with another power post from there another 1/0 cable goes directly to my alternator.
Now if you have a 1 wire alternator that cable will give power when the cut off switch is turned on. I have mine wired to a toggle so I have to manually turn it on.
I am also have a lot of grounds starting with a 1/0 cable coming off the battery going to the frame and a pair of 2 gauge coming off each engine mount to the frame and 2 braided grounds coming off the front of the block and a firewall ground.
Now I also run a DC Power 170 amp alternator and when the car is running with my Intrepid fans on high, my big 300 fuel pump, 16" pusher fan, trans fan, remote water pump and lights on I still see 14 volts at my gauge.
Grant it my set up is overkill for most applications but what Dc Power told me and I have found out myself is all these huge cables get the power where it needs to be with minimal resistance, I even have 2 gauge powering my two auxiliary fuse panels.
