What gauge cable for trunk mounted battery?

["MSI: John Christensen" <JohnC@domain.elided>]

I plan to install an Optima battery in the trunk of my '69 GTV later this
week, but I am not certain what gauge cable to buy for the long run up
front.  I took a look at the stock setup of a late-model Spider and it
*appears* that Alfa used 2 gauge wire (either that, or the insulation was
simply much thicker than the 4 gauge I had on hand for comparison).  Is 4
gauge sufficient, or do I need to drop in some thicker 2 gauge?

Thanks,
John
Seattle, WA
'69 GTV

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