Good to hear that you are making progress, no matter how small. I found I had a similar issue with my temperature gauge, but talking to some people suggested that it was hardly ever heard of (always read lower). My Tiger was definitely not over heating either. I have changed the position of the heater outlet fitting and the temperature probe since. This occurred when I changed to an aluminium inlet manifold. I have also installed a heat insulating gasket to help reduce heat soak, but cannot be avoided with such a small engine bay. One thing that definitely helps is a good quality battery. I installed an Optima battery.
Keep us informed with your progress.
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