Assigning custom ICAO to a real weather station

Hello,

I'd like to know if there would be a way to tweak FsrealWX so as to add a real-world weather station for a fictitious airport. Let me explain.

I am currently making an imaginary airport for the Kerguelen islands close to Port-aux-Français station. This station provides METAR weather data, just like an airport. If I can retrieve this data, could I assign it to the ICAO I created for this airport and thus get real-world weather for this area?