Thanks guyz.
golfvr6 - Breather hose's are all clean, was not alot in them, just a coating, the mesh was quite clean also! (should I completely remove this mesh?)
Just to check, Is there only the one breather hose right? I also cleaned the other hose which goes across the top of the engine into the airbox, that was very clean also!
MK1 - the valve stem seals, is there a way to check these? or is it a big job to replace them?
I did notice that on the new spark plugs (1 week old) that the second one from the left and the 4th one from the left had a black deposit just around the rim where the prongs come from, is this any help?