If you put in any gear and the gear lever still moves in an arc, it will be because the pin in the bottom of the stick + the slot in the front shift rod are worn. Bushes may help a bit, but the only real answer is to find a less worn pin and repair the slot with weld/grinder/files.
If anyone knows where to get replacement pins I'd love to hear...
I am going to drop the engine out to replace the worn gearbox. So I thought I would replace the shift bushes at the same time. Just interested to see where the best quality bushes come from, as I'm only going to do this job once.