A FWIW ?
Thru the years, when ever I've had a need to power up an add-on accessory(s) that has (or might have later) any run distance (?) with a load of up to 20 amps or more (?), I've used enclosed 8/3 wire cord, from the Battery area to the back bumper area. It's Fine [stranded] with Low resistance yet flexible and MUCH EASIER to run and tie off than standard automotive wire(s). Looks better than multiple wires too.
I twist the Load (black) & Neutral (white) wires together to use as
+, the use the Ground (green) for the
-. (Soldered crimp terminals, shrink wrap and a 40 amp Fuse/Breaker block at the Battery(s).) (My preference)
It's a One Time Install that can be used for just about any 12v needs along the run, by just tapping into it.
Joe
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