Shunt location question

[wsaharem]

I'm trying to figure out if I need 1 shunt or 2, or if I need to change my planned wiring to accommodate a shunt.

Current scenario is 2 batteries and 2 stacked inverters connected via a busbar. In this configuration I'm confused if I need 1 or 2 shunts?

Or, should I change the wiring, introduce a 2nd busbar and place 1 shunt between the 2 busbars to track SOC?

Picture shows option 1 (my preferred solution), or option 2, the most logical solution, but adds more wires, connections and possible resistance?

 

[BentleyJ]

With option 1: Use a 500A Smart Shunt and you should be able to run 1 large (or 2 small) cables from the bus bar to the shunt then run 2 cables up to each inverter that originate from the shunt. There is no reason you cannot land 2 lugs on the shunt bolt. It may require getting longer bolts.

EDIT: Would recommend using flexible welding cable or equivalent and using strain relief cable mounts to keep stress off the shunt bolts.