I am trying to connect to Acumatica with the Authorization Flow instead of the Resource Owner Password Flow, which is the only flow I have been able to find examples for. I have tried various subsets of the "URL of the Acumatica ERP instance to which the client application is going to connect" for the <Acumatica ERP instance URL> cited in the Authorization Flow link I posted above as a Service Reference, but none of them seem to get me any endpoints that have anything I could pass a token to (indeed, they all just fail altogether, with variations on a reference that could not be resolved or access not allowed). For reference, the complete URL is https://try.acumatica.com/isv/entity/Default/6.00.001?wsdl&company=(My Company's Name). This works to get the Password Flow, but not the Authorization Flow.
How do I actually implement the Authorization Flow?