[rickst29]

See photo. This older model one lug terminal post for "battery +", a second for "battery -". The limited height of the post, as well as the inability to mount multiple lugs with an offset angle from each each other (to keep the contact surfaces completely flat) means that only on lug can fit.

For the mere "2000w continuous/ 3500w peak" maximum (more like "1600w" continuous if loads attempt draw that power for more than a few seconds) at roughly 93% converter efficiency, your single cable needs to handle roughly 180A. It should be 4/0 AWG. (2/0 if rated for 90c temperature, might be considered OK by some people., but I don't like that wire size if they can't doubled into each port.