A6 BiTdi Tiptronic to DSG Transmission swap
 

Hi, I have a 2014 A6 Allroad BiTdi. The car and the engine are fantastic.
But the transmission is not the same story...
My brother has an A6 3.0 Tdi 245ps S-Tronic, and the shifting is much smoother.
So I'm thinking about changing the transmission when the warranty is over.
I'm hoping this is not to complicated, since the car is deliver with DSG and similar but weaker engine 3.0
My plan was if possible to buy an S-Tronic transmission for the 3.0 Tdi, get upgraded clutch kit for it.
Do a software change/Tuning for the new transmission.

Would it be so simple, or how much more complicated, wiring, shafts?
Thanks in advance!