Yes its a UK spec car and as far as I know the rad is the standard one. 2005 GTI manual AXX block.
I had a look at the link above but it doesn't make a lot of sense to me. I took a pic of the hose in the car and have circled the part, but do I need to put the photo to photobucket (have an account) to be able to post it here?
Parts I have changed are the the thermostat which is inside a big housing that bolts to the block under the inlet manifold, part no V06F121111F. And the Temp sensor above the gearbox on the right of thr engine as you're looking from the front, part no 06A919501A. So there should be one left, the inline one on the turbo hose. Correct? This one, part no 4E0121113, and (I think) is where I've described.