I have a GRT HXr EFIS in my aircraft. Rather than re-entering the flight plan data to my GPS or the EFIS, I would very much like to upload a GPX file.
The AOPA Flight Planner is capable of exporting a gpx file for the active flight plan.
To do this, load the desired flight plan then click on the Route menu, then Send to. Then select Export (GPX) from the options.
This will create a GPX file that you can then use for transferring to your panel GPS.
Here is a screenshot of the menu and export option:
Customer support service by UserEcho