Big Three Question

[tacomabanga1986]

well i got to thinkin over my big three and i came to some questions, ok i have a ground behind the motor goin from engine block to firewall, and i had a ground comein from finder to battery neg witch was small as hell so i replaced it with 0guage, but now i want to finish the big three, can i just replace the wire goin from engin block to firewall with 0guage, or do i halfto run a wire from engin block to battery neg?, and i got new batt terminals that have 0,4,8,8 for pos and neg and how would i go about runnin 2 0guage's to the pos? i was thinkin about gettin one of these and run a 0guage wire from battery pos to it, then one to my fuse holder goin to back battery, n gettin another fuse holder to run from alt to dist block? will this work for a big three? im not runnin that much power just a 1000w sub amp, 300w midbass amp and 300w mids n highs amp, do i really need the big three and my alt is 70amp