I can hear air/gurgling in the heater matrix behind the dash.
Any special requirements for bleeding the system, or is it normal?

No one else had this?

system is self bleeding or should be. worst comes to the worst park the car on an incline or jack the front up, remove the rad cap and run it gently for a while with the heater on. With the rad cap as the highest point it will encourage any air to exit that way. Other than that drain and refill the system

Cheers.