AFAIK, the GTI VW badge and the one on the pre-facelift Golf are different sizes.
Regarding the removal of the badge folks, I tried the twist method and it worked, which I was chuffed about. So no need to remove the grille for me.
Just waiting for the black badge to arrive now!
Although I must say, it looks like its going to require a bit of patience and a steady hand to remove the front face of the existing badge to install the new one.