Rear disc conversion options for mk1's

[pommydubber]

I'm in the middle of my project to turn my cabrio 1982 1.6 into a 20vt beast. I am about to get a 9n3 2007 polo gti from the wreckers as my donor for the engine. I was wondering if anyone knows if the rear end brakes are transferable too?
If not what other options are out there?
Can't seem to find any threads on net apart from rare part mk2 disc conversions. Not much good here in oz!