Thanks for the info.  So the setup I bought came with 2 915mhz radios.  I poked around a little and can get them to power on and made a serial cable to connect it to port B on an FMX.  Do i need an unlock on the FMX to be able to accept correction info this way?  VRS unlock or something?  I think I may order an RTKonnect to tinker with too.