Cost Sharing across multiple Inventory Organizations

Hi All,

I'm trying to share costs across organizations by assigning the same Cost Master Org to 2 different organizations (within the same SOB/Operating Unit). I'm using Standard Costing. When I get to the Cost tab on Organization setup, the Cost Org defaults in as the Org I'm adding and doesn't allow me to change the value.

We already have an Inventory Organization setup and has transactions against it. We want to setup a few more Inventory Organizations that share the cost with the already existing Inventory Organization.

The two item attribute controls 'Costing enabled' and 'Inventory Asset' are set at "Organization Level" and can't updated to "Master" level.