For that milltek you need the correct milltek centre pipe also is all, either that or get an exhaust shop to make you one up to suit your new rear silencer.
Ideally you should have double checked before hand.
As much as I loved the old tg, would I honestly watch clarkson and the gang present a cooking or gardening show...... Errrrr no. I watched for the cars and thus far new tg has that so I'll keep watching. I enjoyed ep 2, would watch again.