Handy to know Mark if someone is looking for a custom setup.
Given my issue with the thinner cable seems to be an isolated one I doubt there will be a rush on the terminals 8>)
I have had plenty of help from the contributors on this thread so rather than just put new cables in, my feedback may avoid a problem fo someone in the future?
I would suggest that if someone's fan was on flat out continuosly, then their cooling may be marginal and they would investigate the cause? I do tend to test modifications quite hard, it gives me that little extra confidence and safety when off roading, in particular in the summer months.