Just a buy a MK6 R.
Be cheaper in the long run.
yeap but ANYONE can do that, too easy.
It's on my list. 
How does yours handle at the moment?
Really REALLY well.
Yes there is too much power for a FWD car but once rolling she's as planted as anything with 4WD. The progressive linear map from R-Tech is the greatest mod I have so that helps. She is still raw compared to a nicely sorted "out of the box" 4WD VW or AUDI but that's one of the attractions for me.
I think £2k all in should be achiveable from start to finish for parts and labour. If I decided to go BT with WMI then I'd def do it.
What about some sticky rubber and a diff? Pikey on here and Ryan from Midnight Garage are running 500+ with just the front wheels driven...
That's the other option and probalby a similar price!