Thanks to everyone for helping me finally pinpoint the third faulty component contributing to lack of smooth (or any!) gear change. Helped for a while by new clutch (after 94K) and new clutch cable, but then 4 weeks later back to pedal too low, almost impossible gear changes etc. Been noisy into reverse for ages - but then hindsight is a wonderful thing isn't it? I had a weld done on the pedal box a few weeks ago, but not enough. The internet is a wonderful thing - just such a relief to see all the car's symptoms in a list with a diagnosis.