Anybody used Flows with UPS?

Has anyone used Flows with UPS API yet? I’m simply trying to push a tracking number Field to UPS and return if Delivered=yes/no to another field. Seems so simple, yet its still so complicated, even with Flows. The documentation for Flows is lacking, and UPS doesn’t know anything about Knack. I think I have the Flow set up properly, its just the strings/headers/body/URL I’m struggling with. Any pros out there that can help?? Thanks!
JD