Re my noisy fan issue. I had a retired mechanic / golf mate look at it in the car park but we had no tools .I don't know yet what caused the vibration and noise but some time ago, before I could grab it, I saw a large tree frog climb down into the rain drainage channel below the windscreen outside. Apparently it lives there. Can a frog get into the air intake from the drain? Is it an interior or exterior job?