I know theses posts were a while ago but having a read of it all, wow what a relief for goat!!

I have a 2010 gu patrol cab chasis with 75,000ks and I'm experiencing the exact same problem and cant figure it out and also the mechanic has gave It a flush but still over heats, maybe coring of the radiator like goat has done should finalise this problem!!!!
just curious goat did you have pressure in the radiator hoses when you had this problem???

any replies would be awesome and great help thanks guys!