I copied this many years ago. I added a 1-0 Gauge welding wire from the trunk to the engine block.
1 gauge wire will work for most with out all the forward electronics, but 1-0 is GOOD overkill. 2-0 is more overkill and not really needed, is extra heavy, but only about 2 pounds more. It is $$$ more too.
The below is just the diameter of the copper, not the sheath. Sheath diameter can be very deceptive.
1 Gauge is 0.289 Inch or 7.35mm
1-0 gauge is 0.325 Inch or 8.25mm
2-0 gauge is 0.365 inch or 9.25mm
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