No bleeding on AU3 AFAIK
. My XR8 has no bleed plug anywhere that I've seen. Procedure according to workshop manual is as follows:
*Fill with coolant up to MIN mark on tank.
*Put cap on, start car and run at 2000rpm for 10 mins - This is to make sure thermostat is fully open and **To ensure air is automatically purged from the system** (air automatically purges back to expansion tankj through the small (8mm?) hose which goes from top R/H radiator tank back to resevoir - and through the other small hose too I figure but the manual doesn't say so.) I kinda figured 1500rpm for 5 min and/or intermittantly until full operating temperature is reached would be ok though (?). BTW I think you can tell thermostat is fully open when fluid starts flowing back into the resevoir through the little hose which comes from the top radiator hose (or thermostat housing on I6 I think). Oh - and heater should be on (or climate control to 32 deg. for this step of course).
*Once car has cooled again, top up level to MAX mark.
(Manual says "This procedure must be followed to ensure correct system performance."