you cant use the 4x4 stuff.
you can use the 2wd stuff tho, but you will need the complete rear beam as the stub axles have a different bolt patter to mk6, unless you can find a mk6 rs2k rear brake setup.
if you can, you need
hubs/stub axles, discs callipers pads and handbrake cable.
if its all off a mk5 then you will need the rear beam aswell
HTH