How do I convert a Trello board member to a single-board guest?

[Scott Garman]

I have two users who are members of my board, but they are single members and would be better classified as guests on that board. How do I convert their status without deleting them?

Thank you in advance!

[Sal]

Hey @Scott Garman! If these two board members you mentioned are already members of only one board within your Workspace, they're already considered single-board Guests (Or Workspace Guests). Unless these users you're referring to have access to multiple boards within your Workspace. In that case, removing them from the additional boards until they can access only one will convert them to single-board Guests. 

[Celine Hau]

no, you first have to remove them from the workspace (not deactivate, just remove access). removing them only from boards won't work.