For this specific case, we thought we needed two collaborative spaces (CS) to separate work and permissions. But during development, we realized that these two spaces were essentially the same. Now having two CSs just adds overhead and a little bit of confusion when resolving save/edit/change permission errors. 

I want to merge all of the content from CS2 into CS1

Is there a straightforward way of migrating all that content in a bulk fashion? Or do I need to go item by item (or chunks of items) and move them?

I think moving References (parts, CAs, whatnot) to another CS will be easy, but I worry about all the Instances and other less visible objects. 

I'd love to make the superfluous CS simply disappear after merging. If it has to stick around afterwards, I imagine I can remove everyone's edit access and they can simply be Readers. New content can be created in the target CS afterwards.

Thoughts?