its simple for the bus-drivers
Ive flown all of the A320-A330-A340 families and I can tell you its simply a push of a button from HDG/V-S to TRK/FPA which is what you asking. Ive had a controller in the Middle East ask me to fly a track around a prohibited area, it went like this:
ATC-Fly Track 270
Pilot-Confirm you mean heading 270?
ATC-Confirm you type is A319
Pilot-track 270 it is.
We had a good laugh that day especially when he reminded me to contact our handling on our second box to get our parking position, because it was some heavy season and if I don't remind them they will throw us in a remote area!