Working on the A10...
Being pressed back into action for the first time in years, you sort of expect a few issues. The only thing that went wrong was the gear change return spring snapping, but did it leave me stranded? Not at all, shoot back home, take off the cover and order a new one. It was there the next day!
So, without further ado... The outer cover comes off easily with four nuts to remove and three screws. The kickstart and gear change can stay attached at this stage and makes it easier to remove the cover. Also, the outer cover can be removed without affecting the gear indexing so makes this a very easy job.
With cover removed, you can see the offending item sticking out behind the gear change mechanism. The split pin, visible here, can stay in place, just remove the tiny circlip from the outer side of the cover and the whole unit will slide out from this side, revealing the spring.