I had another bash and I'm going to cut my losses with the shifter rather than mess with a working one: I can't see how you remove the clip anyway, and even though each time I replace it to what looks like the correct position it still doesn't click in to retain. I wonder if the internal cable routing is the issue, although not enough to waste another hour or two trying to get it right. The really annoying thing is I have a perfectly good 3x9 shimano shifter setup downstairs that won't work with my sram rear mech. Oh well, I shall enjoy a ride out on the zaskar tomorrow instead while I search for a decent 9 speed sram shifter.