George@Fourtitude say they have heard that the 3.6 won't fit in the Golf and probably not in the TT as well.
Futher, he don't think there's currently a transmission or DSG (S-Tronic) built to take the torque of the 3.6........
Read more here.
My TT RS article info comes from Autozeitung.
There is no TT RS 3.6 info from Audi but only a rumour of a 302 hp VR6 TTS.
It is not clear if that is a power upgraded 3.2 litre or a 3.6 litre VR6 engine.