Can the current version of the SDK be used with an old VB6 application? If so, is there any documentation?

I have an old VB6 application that is still in use, but stopped being able to push data into Sage 50 via the SDK since we updated to one of the more recent versions of Sage 50. I downloaded the 2019 version of the SDK and haven't been able to figure out how to set up the reference to the SDK in Visual Studio. I tried searching through the documentation, but there understandably didn't seem to be much documentation for VB6. Does anyone know if there's documentation somewhere where I'm not looking?