hi,
my first post, hope this is useful!
demon tweeks do a manual fan switch, i have fitted one on my rst. handy for track days to reduce heat when stationary, but mostly when your fan switch dies!!! think i'd want to fit one to all my cars from now on. i remeber sitting in traffic, noticing my temp gauge going up and up, so hit the switch and down it comes. if i'd not had it fitted, would have been new head gasket if i'd not noticed it!
only a few quid iirc