with difficulty!. the drivers side top engine mounting has to be removed & you will need to lift the engine with a jack from underneath,to give a bit more clearance, then you will also need to remove anything else that gets in the way. when you've undone the bolts holding the tensioner you then have to turn it & manoeuvre it, to get it in a position where it will clear everything, this is probably the most tricky bit & it's really trial & error. good luck!
jim
January 2010