Is it possible to change dashboard layout with Cloud REST API?

I can create a dashboard and add gadgets to it using the Cloud REST API, but there doesn’t seem to be an API for updating the dashboard’s layout.

The default layout of a dashboard seems to be 2-column and Cloud REST API disallows adding a gadget at position (row: 0, column: 2).

How can I change the layout of a dashboard?

There is this set property API:

But it is unclear what item ID and property key should be, the example provides no list of possible values.