Hey!
The easiest setup for you would be to use Mission Planner as a NTRIP client. You could connect your GCS to the Internet and stream correction data from NTRIP service of your choice, then inject it to the telemetry radio, just like we described in the docs.
Keep in mind, that VRS NTRIP stations require a location feedback from the client. Reach does support this feature, but it works only with directly delivered corrections, not injected. I am not sure about Mission Planner, but it should be there.