[docurley]

One you will need to be quattro to run the 6 speed box and you can not retro fit quattro to your car if you are not.

Moving on you will need to have the whole loom of the S4 if your car is not a face lift as the clocks wont work without it your going to need suspension hubs and swap out the drive shaft with yours to have any chance of linking up your box. Rad should be fine and the speed setup will drop in fine if as I said you are quattro but remember you will need the rear subframe and rear diff and suspension to make this all work.

If you don't want to do the whole loom and that will mean updating the inside to face lift then look at going Standalone ECU.