ItemSetItem - How do I use this?

Hi,

I am attempting to create a "copy" of an existing commerce collection item.
I get the body from /api/Item/itemcode
I replace the ItemCode and ItemId on the actual item property (not the components), however I get a HTTP 500 response.

However if I empty the Components property set/array I can submit without a problem.

Can I please get a working example on how to use this data type while using the components array?

Thank you.