Audi a3 petrol 1.6fsi to 2.0fsi

How difficult is it replace an A3 1.6 fsi with a 2.0.FSI  From other post I have a sportback with a 2.0fsi engine that is US, The garage has advised me not to waste any more money on this car. However I had purchased a 2.0fsi engine, new Gates cambelt kit. VW waterpump and clutch kit, to fit to the replacement engine. I would like to find a 5 door  A3/8p 2.0 with a broken cam belt, these seem hard to find.  It appears there are numerous 1.6 fsi around with high mileage in 5 doors. Is it feasably to replace the engine and gearbox (I have a 6 speed box)  without major rerouting of pipes.  I have the ECU from the original A3.

What else does a BVY engine fit in the Audi range? Must have four doors (Grandchildren). I know I could sell the A3 for £400 as scrap as it has Vienna leather trim, four working doors with electric windows and  Xenum headlights. Plus alloy wheels.