Found the leak at EP this morning due to the good weather. A water hose (the only one not silicone, typical) had a pin prick sized hole in it which under pressure was squirting more than firemans hose.
So, no more leak for now. Also good news is the fuelling. Found out the car's been running mega weak. It's now been sorted which has resulted in a serious gain in bottom end torque and also the cars ability to pull in 5th. I struggled to keep below 80mph on the way home from Stoke this afternoon since the throttle's so damn sensitive! Not sure that'd work with Officer Dibble..