Thanks for that. This confirms there is no spacer/bush.

Shame the threaded area is so short too as I can't use a nylon locking nut and'll have to go shopping for a self-locker - or ladle on the loc-tite

Perhaps OK after all - just looks odd with it all poking out one side!

That metal sleeve should be completely inside the linkage. Whilst you are there, pull it all out and pack the roller bearings with grease, then refit it.

It's too long to fit flush and if were to be shorter the link would then cant in at an angle. I gather the 6mm or so each side clear of the linkage is normal