I should have learnt by now that things are never simple with the Elise. I repaired the split pipe and theres still steam coming from somewhere. My local mechanic has ruled out HGF with a sniff test and seems to think the problem is with the water pump. A quick check through my receipts and the water pump was replaced by Horizon earlier this year so is still under warranty. Already spoken to Horizon and they have agreed to fix it free of charge if its the water pump thats gone.
Making the trek to Birmingham Monday.