Sending a serial stream *to* drone over transmitter

Before going down the rabbit hole, I wondered if anyone had experience with this.

I have a TBS Crossfire TX, and was planning to use a Diversity Nano RX.

The Diversity RX has 8 connectable channels, 1/2 are the RC & Telemetry over CSRF, 3/4 are MAVLINK for Mission Control.

I wanted to use 7/8 (8 being the only other channel listed as serial TX) to send another serial stream (in this case GPS corrections) to the drone from the receiver, either from the same machine that’s running mission planner, or a web server that the NanoTx is connected to.

The manual states it will work as a serial pass though but doesn’t actually say anything about how you configure the data to be sent, has anyone managed to get this working? Ideally, there’d be a nice screen, like with MAVLINK where you point it at a TCP server, but I can’t for the life of me see anything.

I’m open to other suggestions but it would be a lot neater to keep this all-in-one package.