Dan, you're right about there being plenty of room in there! The only reason I fear it is badly warped is that I was rather slow in diagnosing the problem. (should have checked the boards sooner). This was the 3rd time in 2 months I'd had radiator problems, only now connected it to the head gasket, so I'm afraid after overheating it 3 times now, the damage could be bad, but it's certainly worth taking a look at before completely giving up. Only problem is, once you take it apart that rules out the thermalgasket solution, although I'm not convinced that's much of a solution anyway.