FIrst Rover Build- are RTK corrections passed over telemetry radios to Rover from MP?

I am building a prototype rover to validate a control system that can be adapted for an autonomously mow the lawn, spread fertilizer, identify and kill weeds, treat for ants…etc. I am trying to start modestly and build out as needed. I have the basic rover built except for the GPS. I have driven it using a RC radio.

I have not purchased a high precision GPS but plan to purchase the basic ArduSimple kit with the ublox antenna. However I am unclear about a few things.

Can I use my telemetry radios to pass correction data between Mission Planner and the Rover? Or do I need to add another comm path such as BT or WiFi?

I have an NTRIP Caster ~9km away. My goal is to use those corrections vice having to set a local base. I am unsure how Mission Planner uses the correction data. The Wiki seems to indicate two communication paths to the rover for RTK precision data.

Is the PIXHAWK 1 good enough for this task?

I read somewhere that the PIXHAWK 1 was compatible with ArduSimple board. I cannot remember where I read that but I would like to know if anyone has experience using this configuration.

If the setup below works together, without any additional computers, I plan to drive it around all my borders to verify good GPS fixes before adding additional complexities.

The setup is pretty simple.
Flight controller: PIXHAWK 1 (F427 board).
PWM Receiver: FS-IA6B (2.4MHz)
Motor Controller: Sabertooth 2x32 driving 2 brushed wheel chair motors.
Telemetry Radio: 915 Mhz for mavlink
GPS: ardu simple F9P
Antenna: u-blox ANN-MB-00 Antenna
Mission Planner running on an older laptop.

TIA, what a wealth of information on this forum and in the wiki. So much so that it is really overwhelming.

Mission Planner will pass RTCM3 over MavLink on your telemetry radios.