hard to say...depending on how bad the headgasket was, but it might have survived better with the radiator cap off to relieve the pressure in the cooling system and decrease the coolant loss.
I drove one of my Gc's all the way from newcastle to sydney with a blown head gasket...
I took the radiator cap off and turned the heater on flat out and wound the windows down.
It was July tho...and it wasnt a bad gasket blow.
I only stopped twice to add water....I had two 4 litre bottles in the boot.
That F2 head would be like cheese now after being overheated like that
