Oauth Post / JSON command?

I have a working Postman command for an Oauth 2.0 "POST." Separately, I also have a working Oauth 2.0 within Fusion for the same destination using the HTTP Oauth 2.0 connector.

I'm running into trouble trying to convert what I have in Postman, into Fusion.

When I do a HEAD with the HTTP connector, I succeed. Same thing when I do GET with the scope of Read_Sheet.

I copied the body from Postman into POST command in Fusion, calling it RAW and setting it to JSON:

I receive an error, 1004: you are not authorized, which is weird because you have to set the connection first, and it's verified.

I thought maybe I needed to add an "Authentication : Bearer xxxxx" in the header, and that got me an error about expecting HTML.

Other things I've tried: putting all of Postman's code into the Body, same 1004. Putting all of the code in as a Query string, same 1004. Putting just the authentication/bearer into the Query string, same.

I would love to hear any suggestions people may have.